FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

BRENT SHERMAN,                       
             Petitioner-Appellant,
               v.                         No. 05-35364
UNITED STATES PAROLE                        D.C. No.
                                         CV-05-00008-JAR
COMMISSION; ROBERT A. HOOD,
Warden; CHARLES A. DANIELS,                 OPINION
Warden,
           Respondents-Appellees.
                                     
       Appeal from the United States District Court
                for the District of Oregon
       James A. Redden, District Judge, Presiding

                 Argued and Submitted
            March 9, 2006—Portland, Oregon,

                 Filed September 4, 2007

     Before: Melvin Brunetti, Thomas G. Nelson, and
             Richard A. Paez, Circuit Judges.

                Opinion by Judge Brunetti




                          11253
11256        SHERMAN v. U.S. PAROLE COMMISSION
                         COUNSEL

Christine Stebbins Dahl, Assistant Federal Defender, Port-
land, Oregon, for the petitioner-appellant.

Kenneth C. Bauman (brief), Assistant United States Attorney,
Portland, Oregon; and Kelly A. Zusman (argued), Assistant
United States Attorney, Portland, Oregon, for the
respondents-appellees.


                         OPINION

BRUNETTI, Circuit Judge:

   We consider whether an administrative warrant issued pur-
suant to 18 U.S.C. § 4213(a) for the retaking of an alleged
parole violator is subject to the oath or affirmation require-
ment of the Fourth Amendment’s Warrant Clause. We hold it
is not and therefore affirm the denial of petitioner’s habeas
challenge to his detention on an unsworn parole violator war-
rant.

                              I

   Petitioner Brent Sherman is a federal inmate currently
being held by the Bureau of Prisons at the Federal Detention
Center in Sheridan, Oregon. In 1982, he was sentenced to
twenty-years imprisonment for two counts of bank robbery
and one year for failure to appear. In 1985, he escaped and
committed armed robbery of another bank, crimes for which
he received five years and twenty years, respectively. Because
his offenses were committed prior to November 1, 1987, the
effective date of the Sentencing Reform Act of 1984 which
replaced most forms of “parole” with “supervised release,”
Sherman received “old law” sentences under the former statu-
tory regime, which remains in effect as to such offenders. See
             SHERMAN v. U.S. PAROLE COMMISSION           11257
United States v. Kincade, 

, 817 n.2 (9th Cir.
2004) (en banc); Benny v. U.S. Parole Comm’n, 

,
981 n.2 (9th Cir. 2002).

   Paroled for the first time in 1993, Sherman’s parole was
revoked two years later for possession of a controlled sub-
stance, extortion, and unlawful use of a weapon. He was
paroled again in August 1999 and five years later requested
a hearing for early termination under 18 U.S.C. § 4211(c)(1).
See Benny, 295 F.3d at 982-83. Instead of granting his
request, the United States Parole Commission once again ini-
tiated revocation proceedings.

   In November 2004, the Commission issued a parole viola-
tor warrant for Sherman’s retaking pursuant to 18 U.S.C.
§ 4213(a)(2) on the basis of two alleged parole violations:
sexual assault (rape) in 2000, and fraud in 2000 and 2002. It
is undisputed that the warrant application containing the alle-
gations was unsworn. In December 2004, the U.S. Marshals
Service took Sherman into custody on the warrant, and the
following month he filed the underlying habeas petition under
28 U.S.C. § 2241 challenging his detention on the ground that
the warrant was invalid under the Fourth Amendment because
it was not supported by oath or affirmation.

   While his habeas petition was pending, Sherman’s parole
revocation proceedings continued before the Commission.
After a preliminary interview, the interviewing officer recom-
mended a finding of probable cause on the fraud charge, but
not on the sexual assault charge. The Commission apparently
took a somewhat different view. It found probable cause that
Sherman had violated his parole, citing both charges, and con-
tinued to hold him pending a final hearing on revocation.

  Meanwhile, in April 2005 the district court denied Sher-
man’s habeas petition. In a published opinion, Sherman v.
Reilly, 

 (D. Or. 2005), the court held that
Sherman was lawfully detained on an unsworn warrant
11258         SHERMAN v. U.S. PAROLE COMMISSION
because, unlike judicial warrants, parole violator warrants
issued under 18 U.S.C. § 4213(a) are administrative and not
subject to the Warrant Clause of the Fourth Amendment. The
court accordingly declined to extend our decision in United
States v. Vargas-Amaya, 

 (9th Cir. 2004), in
which we held that a supervised release “warrant” within the
meaning of 18 U.S.C. §§ 3583(i) and 3606 must comply with
the Warrant Clause. Sherman timely appealed.

   Before the parties filed their briefs on appeal, however, the
Commission revoked Sherman’s parole based on the fraud
charge while making no findings concerning the sexual
assault charge. He remains incarcerated with a presumptive
re-parole date of October 13, 2007. The projected full-term
date on his aggregate sentence is November 25, 2015.

                               II

   The Government asserted below that Sherman’s habeas
petition challenging his detention on the unsworn parole vio-
lator warrant became moot when the Commission conducted
a preliminary hearing and found probable cause that Sherman
violated his parole. It also asserted mootness in its brief on
appeal, by then predicating the argument on the Commis-
sion’s intervening revocation of Sherman’s parole. At oral
argument, however, the Government conceded that this case
is within the “capable of repetition, yet evading review”
exception to the mootness doctrine. Undertaking our indepen-
dent obligation to determine our subject-matter jurisdiction in
the face of possible mootness, see Dittman v. California, 

, 1025 (9th Cir. 1999), we find the Government’s
concession to be well taken.

   The capable of repetition, yet evading review exception has
been applied to permit appellate review of constitutional or
statutory challenges to pretrial and other initial proceedings
despite the regular progression of further proceedings making
it “no longer possible to remedy the particular grievance giv-
              SHERMAN v. U.S. PAROLE COMMISSION           11259
ing rise to the litigation.” United States v. Howard, 

, 1009 (9th Cir. 2007). For instance, in Gerstein v. Pugh,

, 110 n.11 (1975), the Court determined that the
respondents’ convictions did not preclude review of their
challenge to their pretrial detentions, which lacked a judicial
determination of probable cause. In Howard, 480 F.3d at
1009-10, we applied Gerstein and held that the conclusion of
pretrial proceedings did not preclude us from reviewing a
courtroom security policy of shackling pretrial detainees dur-
ing initial appearances. And in United States v. Woods, 

, 896 (9th Cir. 1993), we applied the exception to an
inmate’s challenge to the revocation of his conditional release
under 18 U.S.C. § 4246(f), despite the fact his confinement at
the time of appeal was “not due to the revocation order being
challenged.” By the time we heard his appeal, Woods had
been again granted conditional release and then re-confined
under another revocation order.

   As in those contexts, a parolee’s initial detention solely on
the authority of a parole violator warrant is by nature tempo-
rary and is “not likely to persist long enough to allow for the
completion of appellate review” before the Commission either
releases the parolee or takes further action providing super-
ceding authority for the detention. Woods, 995 F.2d at 896;
accord Gerstein, 420 U.S. at 110 n.11. Indeed, a parole viola-
tor summoned or retaken under 18 U.S.C. § 4213 is entitled
to a preliminary hearing on probable cause “without unneces-
sary delay” and a revocation hearing “within sixty days of
such determination of probable cause.” Id. § 4214(a)(1)(A),
(B). As this case exemplifies, these statutory requirements vir-
tually guarantee the revocation process will be concluded
before appellate review of the initial retaking is feasible.

   This case is also capable of repetition. The Parole Commis-
sion has not retreated from its policy of issuing warrants
based on unsworn allegations, and Sherman is scheduled for
presumptive re-parole in October 2007 with over eight years
remaining on his sentence. During that period of release, his
11260         SHERMAN v. U.S. PAROLE COMMISSION
liberty will continue to be conditioned on the Commission’s
ability to issue a parole violator warrant and retake him based
on unsworn allegations. Cf. Woods, 995 F.2d at 896 (applying
the exception where the defendant remained subject to a con-
ditional release order, the violation of which led to the revoca-
tion order on appeal); Spencer v. Kemna, 

, 18
(1998) (holding that the exception did not apply because the
expiration of petitioner’s sentence negated any reasonable
expectation of another round of parole and revocation). More-
over, because the Commission’s policy is ongoing and gener-
ally applicable to all federal parolees subject to retaking, the
proper construction of 18 U.S.C. § 4213(a) in relation to the
Fourth Amendment is “an issue of continuing and public
importance.” Woods, 995 F.2d at 896.

   [1] For these reasons we agree with the parties that Sher-
man’s appeal from the denial of his habeas petition should not
be dismissed as moot. We hold that despite the Parole Com-
mission’s issuance of a revocation order providing superced-
ing authority for Sherman’s present confinement, we have
jurisdiction to review his initial retaking and detention on a
parole violator warrant under the exception for cases that are
“capable of repetition, yet evading review.”

                              III

   [2] The Fourth Amendment rights of parolees are hardly
uncharted waters. By now it is clear that parolees are pro-
tected against unreasonable searches and seizures. Samson v.
California, 

, 2197, 2198 n.2 (2006); Latta v.
Fitzharris, 

, 248-49 (9th Cir. 1975) (en banc).
But their rights also are not coextensive with those of ordinary
citizens. We have held that “probable cause is not required to
arrest a parolee for a violation of parole. Warrantless arrests
of parole violators are also valid.” United States v. Butcher,

, 814 (9th Cir. 1991).

   Sherman’s habeas petition raises a closely related yet dis-
tinct question: When the United States Parole Commission
               SHERMAN v. U.S. PAROLE COMMISSION             11261
issues a parole violator warrant pursuant to 18 U.S.C.
§ 4213(a) for the retaking of a federal parolee, must that war-
rant comply with the Warrant Clause of the Fourth Amend-
ment and therefore be “supported by Oath or affirmation”?
Because the question has both statutory and constitutional
dimensions, we consider first whether Congress incorporated
the Fourth Amendment definition of a “warrant” into § 4213
before addressing whether compliance with the Warrant
Clause is otherwise constitutionally required.

                                 A

   [3] Although we have interpreted 18 U.S.C. § 4213(a) in
other contexts, e.g., Benny v. U.S. Parole Comm’n, 

, 985 (9th Cir. 2002) (addressing the Commission’s dis-
cretionary power to issue a warrant instead of a summons),
we have yet to address whether § 4213 requires a parole vio-
lator warrant to be supported by sworn facts. “In construing
a statute as a matter of first impression, we first look to the
statutory language: ‘The starting point in interpreting a statute
is its language, for if the intent of Congress is clear, that is the
end of the matter.’ ” United States v. Morales-Alejo, 

, 1105 (9th Cir. 1999) (quoting Good Samaritan Hosp.
v. Shalala, 

, 409 (1993)). Section 4213 provides:

    (a) If any parolee is alleged to have violated his
    parole, the Commission may—

         (1) summon such parolee to appear at a
         hearing conducted pursuant to section
         4214; or

         (2) issue a warrant and retake the parolee
         as provided in this section.

    (b) Any summons or warrant issued under this sec-
    tion shall be issued by the Commission as soon as
11262        SHERMAN v. U.S. PAROLE COMMISSION
    practicable after discovery of the alleged violation,
    except when delay is deemed necessary . . . .

    (c) Any summons or warrant issued pursuant to this
    section shall provide the parolee with written notice
    of—

         (1) the conditions of parole he is alleged to
         have violated as provided under section
         4209;

         (2) his rights under this chapter; and

         (3) the possible action which may be taken
         by the Commission.

    (d) Any officer of any Federal penal or correctional
    institution, or any Federal officer authorized to serve
    criminal process within the United States, to whom
    a warrant issued under this section is delivered, shall
    execute such warrant by taking such parolee and
    returning him to the custody of the regional commis-
    sioner, or to the custody of the Attorney General, if
    the Commission shall so direct.

18 U.S.C. § 4213 (italics added).

   On its face, despite setting forth several requirements for
the issuance of a parole violator warrant, § 4213 makes no
mention of an oath or affirmation requirement. Instead, sub-
section (a) expressly authorizes the Commission to issue a
warrant upon a mere allegation of a parole violation. The stat-
ute’s only other express requirements regard the issuer (“the
Commission”), the timing (“as soon as practicable after dis-
covery of the alleged violation”), and the contents of the war-
rant (“written notice” of the alleged violation, the parolee’s
rights, and possible consequences). Id. § 4213(a)-(c). The
implementing regulation is in accord, adding only that “satis-
              SHERMAN v. U.S. PAROLE COMMISSION           11263
factory evidence” of the alleged violation is required. 28
C.F.R. § 2.44(a).

   Nevertheless, Sherman contends that we should read the
lone term “warrant” as implicitly incorporating the Fourth
Amendment definition. For this argument he relies on United
States v. Vargas-Amaya, 

 (9th Cir. 2004), a
supervised release case in which we interpreted the term
“warrant” in 18 U.S.C. § 3583(i) as manifesting Congress’
intent to incorporate the requirements of the Warrant Clause.
He also invokes the general principle of statutory construction
that the same language should be given a consistent interpre-
tation across different statutes, citing Leocal v. Ashcroft, 

, 11 (2004).

   While we do not necessarily disagree with either premise,
the issue is not so simple. Considering isolated terms without
regard to the complete statutory language can be misleading,
as can narrowly focusing on the holding of our opinions with-
out due regard to the intricacies of our reasoning. Certainly
Vargas-Amaya is a highly relevant precedent here given obvi-
ous similarities between the issues presented. But closer
examination of that opinion reveals a textual analysis of the
supervised release statutes that, when applied to the distinct
language of the parole statutes, leads to precisely the opposite
result.

                               1

   In Vargas-Amaya we addressed whether the district court
lacked jurisdiction under § 3583(i) to revoke supervised
release after the release term had expired because the warrant
on which the defendant was arrested was not supported by
oath or affirmation. That statute provides:

    The power of the court to revoke a term of super-
    vised release for violation of a condition of super-
    vised release, and to order the defendant to serve a
11264        SHERMAN v. U.S. PAROLE COMMISSION
    term of imprisonment and . . . a further term of
    supervised release, extends beyond the expiration of
    the term of supervised release . . . if, before its expi-
    ration, a warrant or summons has been issued on the
    basis of an allegation of such a violation.

18 U.S.C. § 3583(i) (italics added). Focusing narrowly on the
word “warrant,” we invoked two canons of statutory construc-
tion: “in the absence of a statutory definition, a term should
be accorded its ordinary meaning”; and “when Congress uses
a term of art, such as ‘warrant,’ unless Congress affirmatively
indicates otherwise, we presume Congress intended to incor-
porate the common definition of that term.” Vargas-Amaya,
389 F.3d at 904. Accordingly, at the outset we presumed that
Congress “incorporated the Fourth Amendment’s prohibition
against the issuance of warrants based on something less than
probable cause supported by sworn facts,” and agreed with
petitioner that “the plain meaning of the term ‘warrant’ means
a document that is based upon probable cause and supported
by sworn facts.” Id.; see also U.S. Const. amend. IV (“no
Warrants shall issue, but upon probable cause, supported by
Oath or affirmation”).

   But that is only the tip of the iceberg. As we also noted,
these canons of statutory construction may be overcome if
“Congress affirmatively indicates otherwise” or gives “ ‘con-
trary direction.’ ” Vargas-Amaya, 389 F.3d at 904 (quoting
Carter v. United States, 

, 264 (2000)). In other
words, the presumption is rebuttable and therefore requires
consideration of the statutory context and the surrounding
terms. After all, terms do not appear in isolation and a stat-
ute’s remaining language may place its terms of art in a dif-
ferent light and alter the plain meaning of the statue as a
whole. See Leocal, 543 U.S. at 9. Of course, after accordingly
expanding our analysis of the supervised release statutes in
Vargas-Amaya, we happened to find confirmation of the pre-
sumption rather than contrary direction. But because our opin-
ion in that case is fundamentally one of statutory construction
              SHERMAN v. U.S. PAROLE COMMISSION           11265
and we dealt with an entirely separate statutory scheme, our
methodology rather than our conclusion is more pertinent to
our analysis here.

   Perhaps most remarkable about our analysis is that, despite
initially applying the aforementioned presumptions regarding
the implied meaning of the term “warrant,” we went on to
determine that § 3583(i) “does not relate to the requirements
for issuing a warrant at all.” Vargas-Amaya, 389 F.3d at 906.
In considering the operative phrase “if, before its expiration,
a warrant or summons has been issued on the basis of an alle-
gation of such a violation,” 18 U.S.C. § 3583(i), we rejected
the Government’s contention that the “allegation” clause had
the effect of narrowly defining the term “warrant” as “some-
thing less than that required by the Fourth Amendment.”
Vargas-Amaya, 389 F.3d at 905-06. We reasoned that Con-
gress’ use of the past tense in § 3583(i) (“has been issued”)
rather than the present tense (“[may be] issued”) indicates that
§ 3583(i) merely enumerates the prior issuance of a valid
supervised release warrant as a jurisdictional prerequisite
without prescribing the requirements for issuing such a war-
rant. Id. For those requirements we looked instead to § 3606,
in which Congress did use the present tense in discussing the
issuance of such warrants.

       Congress’ use of the past tense [in § 3583(i)]
    stands in contrast to the Fourth Amendment, and
    Rules 4, 9, and 41 of the Federal Rules of Criminal
    Procedure all of which discuss the requirements for
    issuing an arrest warrant in the present tense. See
    U.S. Const. amend. IV (“no Warrants shall issue”);
    Fed. R. Crim. P. 4(a) (“the judge must issue an arrest
    warrant”); Fed. R. Crim. P. 9(a) (“The court must
    issue a warrant”); Fed. R. Crim. P. 41(d) (“a magis-
    trate judge or a judge . . . must issue the warrant if
    there is probable cause”). The use of the past tense
    in § 3583(i) implies that the statute does not relate to
    the requirements for issuing a warrant at all, but
11266         SHERMAN v. U.S. PAROLE COMMISSION
    rather solely pertains to the court’s jurisdiction if an
    arrest warrant has already been validly issued.
    Another statute describes in the present tense when
    an arrest warrant may be issued for a violation of
    supervised release and provides that “If there is
    probable cause to believe that a . . . person on super-
    vised release has violated a condition of his . . .
    release, . . . the court . . . may issue a warrant for the
    arrest of a . . . releasee for violation of a condition
    of release.” 18 U.S.C. § 3606.

Id. at 906; accord United States v. Garcia-Avalino, 

, 446 n.3 (5th Cir. 2006) (stating that § 3583 is a jurisdic-
tional provision while “section 3606 actually governs the issu-
ance of warrants for the arrest of probationers or supervised
releasees”)

   Of course, despite our determination that § 3583(i) itself is
not controlling regarding the meaning of the term “warrant,”
§ 3606 confirmed the presumption that Congress intended to
incorporate the Fourth Amendment definition. Reasoning that
§§ 3583(i) and 3606 must be read consistently regarding the
definition of a supervised release “warrant” and noting that
§ 3606 includes an express “probable cause” requirement, we
concluded:

    The only reasonable inference is that Congress was
    aware of the Fourth Amendment and incorporated its
    requirement that a warrant be based “upon probable
    cause” in both statutes. By extension, if Congress
    intended to incorporate the “probable cause” portion
    of the Warrant Clause in each statute, it must have
    also intended to incorporate the “Oath or affirma-
    tion” portion of the Clause.

Vargas-Amaya, 389 F.3d at 905 n.2.
              SHERMAN v. U.S. PAROLE COMMISSION            11267
                               2

   The plain language of § 4213 may seem superficially simi-
lar to the supervised release statutes we considered in Vargas-
Amaya, but on closer inspection it is structurally and substan-
tively distinct and not amenable to the same inferences. We
therefore cannot reach the same conclusion that Congress
intended to incorporate the requirements of the Warrant
Clause of the Fourth Amendment.

   To begin, by our reasoning in Vargas-Amaya, § 4213’s
plain language makes it comparable not with § 3583(i) but
with § 3606 insofar as the statute itself prescribes the require-
ments for issuing a valid warrant. Congress’ use of the present
tense throughout § 4213(a)-(c) (“the Commission may . . .
issue a warrant,” “Any . . . warrant . . . shall be issued,” and
“Any . . . warrant . . . shall provide”) stands in stark contrast
to the past tense construction of § 3583(i) and instead paral-
lels the present tense construction of § 3606 and Federal
Rules of Criminal Procedure 4(a), 9(a), and 41(d).

   But that is also where any parallels end. Read in context,
Congress did not use the term “warrant” in the same sense in
both regimes. Section 4213 expressly authorizes only “the
Commission” to issue a parole violator “warrant” and thereby
provides for an administrative warrant. 18 U.S.C. § 4213(a).
Only in replacing parole with supervised release did Congress
shift issuing authority to “the court” and thereby use the term
“warrant” in the ordinary sense of a judicial warrant. 18
U.S.C. § 3606; see Gozlon-Peretz v. United States, 

, 400-01 (1991); see also Fed. R. Crim. P. 4(a) (“the
judge”); Fed. R. Crim. P. 9(a) (“The court”); Fed. R. Crim. P.
41(d)(1) (“a magistrate judge”). In certain circumstances the
distinction can be significant. See Griffin v. Wisconsin, 

, 877-78 (1987) (distinguishing between “administra-
tive search warrants” and “constitutionally mandated judicial
warrants”); Abel v. United States, 

, 232 (1960)
(characterizing a deportation arrest warrant under the Immi-
11268         SHERMAN v. U.S. PAROLE COMMISSION
gration and Nationality Act of 1952 as “an administrative
warrant, not a judicial warrant within the scope of the Fourth
Amendment”); United States ex rel. Randazzo v. Follette, 

, 1322 (2d Cir. 1969) (holding that a parole violator
warrant designated as “administrative” under New York law
was not subject to ordinary Fourth Amendment safeguards).
Thus, we question the present applicability of the “term of
art” presumption we applied in Vargas-Amaya where “war-
rant” was used in the judicial sense.

   Moreover, in § 4213 Congress omitted any express refer-
ence to the Warrant Clause’s requirements in describing the
issuance of a parole violator warrant. By contrast, § 3606 and
Rules 4, 9, and 41 all expressly require “probable cause” for
the issuance of an arrest warrant. See 18 U.S.C. § 3606
(“probable cause to believe that a probationer or a person on
supervised release has violated a condition of his probation or
release”); Fed. R. Crim. P. 4(a) (“probable cause to believe
that an offense has been committed”); Fed. R. Crim. P. 9(a)
(“probable cause that an offense has been committed”); Fed.
R. Crim. P. 41(d)(1) (“probable cause to search for and seize
a person or property”). Additionally, Rules 4, 9, and 41 also
contain clear references to a sworn facts requirement. See
Fed. R. Crim. P. 4(a) (referencing “the complaint or one or
more affidavits filed with the complaint”); Fed. R. Crim. P.
9(a) (“one or more affidavits accompanying the informa-
tion”); Fed. R. Crim. P. 41(d) (“an affidavit or other informa-
tion,” which may consist of “sworn testimony”).

   The unique omission of any such references to the Warrant
Clause in § 4213 is significant. In Vargas-Amaya we inter-
preted the express “probable cause” requirement within
§ 3606 as an implicit incorporation of the full Warrant Clause,
which we then imputed to § 3583(i). 389 F.3d at 904-05 &
n.2. The same premise is simply not available to us in the case
of § 4213. Congress’ use of the term “warrant” is accompa-
nied by several express requirements for its valid issuance, yet
none reference the Warrant Clause. While § 3606 and the
              SHERMAN v. U.S. PAROLE COMMISSION            11269
Federal Rules exemplify Congress’ ability to reference and
incorporate the Warrant Clause’s requirements when
intended, the omission of such requirements and inclusion of
others in § 4213 indicates a contrary intent.

   [4] The natural reading of § 4213 is that the Commission
is authorized to issue a parole violator warrant “[i]f any paro-
lee is alleged to have violated his parole”—period. 18 U.S.C.
§ 4213(a). Although in Vargas-Amaya we determined that
§ 3583(i)’s “allegation” clause was largely irrelevant because
of the statute’s past-tense construction, the converse is true
here. Indeed, we expressly noted in Vargas-Amaya that if
Congress were to use the present tense in conjunction with an
allegation clause, that would indicate its intent to require only
an allegation of a parole violation rather than full satisfaction
of the Fourth Amendment:

    The government argues that Congress specifically
    defined warrant as something less than that required
    by the Fourth Amendment—and, thus, that a warrant
    based on unsworn facts is acceptable—because of
    the phrase “on the basis of an allegation of” a viola-
    tion of supervised release. 18 U.S.C. § 3583(i) . . . .
    To effect its reading of the statute, the government
    asks us to rewrite § 3583(i) to mean that “a warrant
    or summons [may be] issued on the basis of an alle-
    gation of such a violation.” However, we are not at
    liberty to rewrite the words chosen by Congress.

Vargas-Amaya, 389 F.3d at 905-06 (brackets in original). Of
course, neither are we at liberty to rewrite the words chosen
by Congress as to § 4213(a), which actually contains a “may
issue” construction. Thus, by Vargas-Amaya’s reasoning, we
must adopt as to § 4213(a) the very reading we rejected as to
§ 3583(i).

                               3

  Contrary to our suggestion in Vargas-Amaya, 389 F.3d at
904, congressional authorization for the issuance of warrants
11270        SHERMAN v. U.S. PAROLE COMMISSION
outside the scope of the Fourth Amendment’s Warrant Clause
is not unprecedented. For instance, as noted above, in 1960
the Supreme Court interpreted former INA § 242(a), 8 U.S.C.
§ 1252(a), as “giving authority to the Attorney General or his
delegate to arrest aliens pending deportation proceedings
under an administrative warrant, not a judicial warrant within
the scope of the Fourth Amendment.” Abel, 362 U.S. at 232.
Much like § 4213, the immigration statute as it then existed
authorized an executive official to issue an arrest warrant
without reference to any Warrant Clause requirements.

    Pending a determination of deportability in the case
    of any alien . . . , such alien may, upon warrant of
    the Attorney General, be arrested and taken into
    custody. Any such alien taken into custody may, in
    the discretion of the Attorney General and pending
    such final determination of deportability, (1) be con-
    tinued in custody; or (2) be released under bond in
    the amount of not less than $500 with security
    approved by the Attorney General, containing such
    conditions as the Attorney General may prescribe; or
    (3) be released on conditional parole. But such bond
    or parole . . . may be revoked at any time by the
    Attorney General, in his discretion, and the alien
    may be returned to custody under the warrant which
    initiated the proceedings against him and detained
    until final determination of his deportability . . . .

8 U.S.C. § 1252(a) (1976) (emphasis added); Immigration and
Nationality Act of 1952, Pub. L. No. 82-414, § 242(a), 66
Stat. 163, 208-09 (1952). Indeed, deportation statutes going
back to 1798 “have ordinarily authorized the arrest of deport-
able aliens by order of an executive official,” evidencing an
“overwhelming historical legislative recognition of the propri-
ety of administrative arrest for deportable aliens.” Abel, 362
U.S. at 233.

  The same can be said of administrative arrests of parole
violators, which Congress has authorized on the warrant of an
              SHERMAN v. U.S. PAROLE COMMISSION            11271
executive official without requiring compliance with the
Fourth Amendment’s Warrant Clause since the inception of
federal parole in 1910. Parolees are legislatively “assigned to
a unique status in our legal system.” United States v. Polito,

, 54 (2d Cir. 1978). “A parolee is a convicted
criminal who has been sentenced to a term of imprisonment
and who has been allowed to serve a portion of that term out-
side prison walls” while subject to various conditions of
release. Id. Under the original 1910 Act, though not in physi-
cal custody, a parolee was “to remain, while on parole, in the
legal custody and under the control of the warden of such
prison from which paroled . . . until the expiration of the term
or terms specified in his sentence.” Act of June 25, 1910, ch.
387, § 3, 36 Stat. 820 (codified at 18 U.S.C. § 716). Thus, a
parole violator was viewed by Congress not as an ordinary
citizen subject to arrest under a judicial warrant but as a “pris-
oner” subject to administrative “retaking” by the warden
already having legal custody over him. As amended in 1930
with only technical changes, 18 U.S.C. § 717, the original
predecessor to today’s § 4213, provided:

    If the warden of the prison or penitentiary from
    which said prisoner was paroled or the Board of
    Parole or any member thereof shall have reliable
    information that the prisoner has violated his parole,
    then said warden, at any time within the term or
    terms of the prisoner’s sentence, may issue his war-
    rant to any officer hereinafter authorized to execute
    the same for the retaking of such prisoner.

18 U.S.C. § 717 (1946); Act of June 25, 1910, ch. 387, § 4,
36 Stat. 820 (original enactment); Act of May 13, 1930, ch.
255, § 1, 46 Stat. 272 (amendment).

   Courts interpreting this legislation soundly rejected
attempts by parole violators to claim certain rights enjoyed by
ordinary citizens. In 1923, the Supreme Court characterized
the nature of parole by stating that “[w]hile this is an amelio-
11272         SHERMAN v. U.S. PAROLE COMMISSION
ration of punishment, it is in legal effect imprisonment” and
that a parole violator’s “status and rights were analogous to
those of an escaped convict.” Anderson v. Corall, 

, 196 (1923). Accordingly, in the 1930s the Fourth and
D.C. Circuits relying on Anderson denied the habeas petitions
of two parolees who, like Sherman, challenged their deten-
tions on unsworn warrants. Both circuits squarely held that a
parole violator warrant issued under § 717 need not be sup-
ported by oath or affirmation. Jarman v. United States, 

, 311 (4th Cir. 1937); Story v. Rives, 

,
188 (D.C. Cir. 1938) (also rejecting the claim that probable
cause was required); see also United States ex rel. Nicholson
v. Dillard, 

, 96 (4th Cir. 1939) (“Nothing in any
statute requires anything more; and in the reason of the case
nothing more was required.”). Despite Congress’ use of the
term “warrant” in § 717, the Fourth Circuit clearly stated that
“the warrant in question was not a warrant . . . as contem-
plated in the Fourth Amendment to the Constitution.” Jarman,
92 F.2d at 311.

   If, contrary to this interpretation, Congress had actually
intended to incorporate the Warrant Clause’s requirements, it
could have expressed that intent in subsequent legislation. But
despite recodifying the parole statutes in 1948, Congress
made no such changes. Like the 1910 Act, the 1948 Act con-
tinued to provide that a “parolee shall . . . remain, while on
parole, in the legal custody and under the control of the Attor-
ney General,” and that “[a] warrant for the retaking of any
United States prisoner who has violated his parole, may be
issued only by the Board of Parole or a member thereof” and
shall be executed “by taking such prisoner and returning him
to the custody of the Attorney General.” Act of June 25, 1948,
ch. 645, 62 Stat. 854-55 (codified at 18 U.S.C. §§ 4203, 4205
and 4206, respectively). Even such a conspicuous change as
the omission of the “reliable information” clause from former
§ 717 was later dismissed by at least one court as “probably
a drafting oversight” given the lack of any “express reference
of congressional intent that would indicate that the change
               SHERMAN v. U.S. PAROLE COMMISSION             11273
was intentional.” Hyser v. Reed, 

, 241 n.11 (D.C.
Cir. 1963) (en banc).

   Given this legislative consistency, courts applying the 1948
Act maintained the view that Congress did not intend parole
violator warrants to be within the scope of the Fourth Amend-
ment, even despite growing recognition that parolees had
some procedural due process rights in revocation proceedings.
For instance, in an apparent departure from the Supreme
Court’s “escaped convict” analogy in Anderson, the D.C. Cir-
cuit observed in Hyser that “in providing for a warrant type
of procedure for retaking parolees thought to have violated
parole conditions, Congress has recognized the need for some
minimal procedural safeguards,” and that “something more
than casual processes or varying improvisations was intend-
ed.” Id. at 242, 244. Yet the court still stopped short of requir-
ing compliance with the Fourth Amendment. Characterizing
a parole violator warrant as an “administrative arrest war-
rant,” the court observed that “Congress evinced no intent to
require precisely the same formalities and safeguards as to
those contained in the Constitution for criminal arrests,” and
it reaffirmed the view that “Congress meant to provide . . .
[that] the retaking [of a parole violator] is not ‘an arrest within
the meaning of the constitutional provisions.’ ” Id. at 241, 244
(quoting Story, 97 F.2d at 188). Accordingly, while the court
proceeded to prescribe in detail various requirements for the
issuance of a parole violator warrant, including “a written
application . . . reciting the facts believed to constitute a viola-
tion” and that “the facts recited . . . , if true, amount to satis-
factory evidence that parole conditions have been violated,”
neither probable cause nor oath or affirmation were ever men-
tioned. Id. at 245; see also id. at 241 & n.12 (discussing the
meaning of “satisfactory evidence”).

   Even when Congress finally did respond to court decisions
by codifying certain judicially-recognized due process rights
of parolees, it again made no changes to bring parole violator
warrants within the scope of the Fourth Amendment. The
11274         SHERMAN v. U.S. PAROLE COMMISSION
Parole Commission and Reorganization Act, Pub. L. No. 94-
233, 90 Stat. 219 (1976), was Congress’ final recodification
and comprehensive amendment to the parole statutes before
the 1984 repeal, and it produced the provisions we construe
today. It was intended in part to legislatively address the
Supreme Court’s then-recent decision in Morrissey v. Brewer,

 (1972), which declared that a parolee’s interest
in his conditional liberty is protected by the Fourteenth
Amendment and prescribed certain minimum procedural safe-
guards for the revocation process. Id. at 482-83, 484-85; S.
Rep. No. 94-369, at 15 (1975), as reprinted in 1976
U.S.C.C.A.N. 335, 337. The Court’s prescriptions included,
among other things, notice of the alleged parole violations and
the parolee’s rights; an opportunity for a prompt informal pre-
liminary hearing near the place of arrest, at which an indepen-
dent administrative officer must determine whether probable
cause exists for the parolee’s continued detention pending a
final decision on revocation; and an opportunity for a final
hearing — not rising to the level of a criminal trial — to
determine whether revocation is warranted. Morrissey, 408
U.S. at 485-89. Congress accordingly codified these safe-
guards at 18 U.S.C. §§ 4213(c) (notice) and 4214 (preliminary
and final hearings). Parole Commission & Reorganization Act
§ 2, 90 Stat. at 228-30.

   Notably, however, neither the Supreme Court nor Congress
suggested that stricter procedures were required for the issu-
ance of a parole violator warrant for a parolee’s initial arrest.
In Morrissey, despite tempering Anderson’s strong-form ver-
sion of the “custody” theory, the Court nonetheless reaffirmed
that “parole is an established variation on imprisonment of
convicted criminals” and continued to give due recognition of
that special status as limiting the rights of parolees as com-
pared to ordinary citizens. 408 U.S. at 477, 480, 483; see also
Samson v. California, 

, 2198-99 & n.2 (2006).
And nearly all of the new safeguards prescribed by the Court
and codified by Congress regard only the process due a paro-
lee in revocation proceedings after he is retaken. See D’Amato
              SHERMAN v. U.S. PAROLE COMMISSION           11275
v. U.S. Parole Comm’n, 

, 75-76 (2d Cir. 1988);
S. Rep. No. 94-369, at 18, 25-26, as reprinted in 1976
U.S.C.C.A.N. at 339, 347-48; H.R. Rep. No. 94-838, at 33-34
(1976), as reprinted in 1976 U.S.C.C.A.N. 351, 365-66. Even
the notice requirement, which does relate to the warrant pro-
cedures, merely relates to the content of the warrant rather
than the justification for its issuance.

   For our purposes, the 1976 Act is practically indistinguish-
able from the 1910 and 1948 Acts in authorizing the retaking
of a parole violator on an administrative warrant outside the
scope of the Fourth Amendment. Much like former 18 U.S.C.
§§ 716 and 717 (1910-1948) and former 18 U.S.C. §§ 4203,
4205 and 4206 (1948-1976), the latest parole statutes continue
to provide that “[a] parolee shall remain in the legal custody
and under the control of the Attorney General,” and that “[i]f
any parolee is alleged to have violated his parole, the Com-
mission may . . . issue a warrant and retake the parolee” “by
taking such parolee and returning him to the custody of the
regional commissioner, or to the custody of the Attorney Gen-
eral.” 18 U.S.C.A. §§ 4210(a), 4213(a), (d) (West Supp.
2007); Parole Commission & Reorganization Act § 2, 90 Stat.
at 226-28.

   [5] Although the 1976 Act did incorporate for the first time
an express “probable cause” requirement for revocation pro-
ceedings, it has no bearing on the issuance and execution of
a parole violator warrant. The term appears not in § 4213 but
in § 4214, which expressly applies only after a parolee has
already been “summoned or retaken under section 4213.” 18
U.S.C.A. § 4214(a)(1)(A) (West Supp. 2007); see also H.R.
Rep. No. 94-838, at 34, as reprinted in 1976 U.S.C.C.A.N. at
366 (“following the issuance of a summons or warrant”).
While § 4214 entitles a retaken parolee to “a preliminary
hearing . . . to determine if there is probable cause to believe
that he has violated a condition of his parole,” that inquiry is
intended not as a post-hoc examination of the warrant’s valid-
ity but to determine whether the circumstances justify “incar-
11276         SHERMAN v. U.S. PAROLE COMMISSION
ceration of the parolee pending further revocation
proceedings,” among other options. 18 U.S.C.A.
§ 4214(a)(1)(A) (West Supp. 2007); see also S. Rep. No. 94-
369, at 18, as reprinted in 1976 U.S.C.C.A.N. at 339. Thus,
the 1976 Act requires probable cause as a prerequisite only
for continuing revocation proceedings beyond the preliminary
hearing and extending a retaken parolee’s detention, not to
compel an alleged parole violator’s appearance at such a hear-
ing. Cf. Gerstein v. Pugh, 

, 113-14 (1975) (hold-
ing with respect to an ordinary criminal defendant that “the
Fourth Amendment requires a judicial determination of prob-
able cause as a prerequisite to extended restraint of liberty fol-
lowing arrest”). Congress certainly could have included
“probable cause” in both §§ 4213 and 4214, but it opted not
to.

   [6] Instead, for the first time Congress expressly referenced
a mere allegation as the necessary predicate for issuing a
parole violator warrant. Compare 18 U.S.C. § 4213(a) (West
Supp. 2007) (“is alleged to have violated his parole”) with 18
U.S.C. § 4205 (1970) (“has violated his parole”) and id. § 717
(1946) (“reliable information that the prisoner has violated his
parole”). The legislative history also repeatedly mentions an
allegation as a sufficient predicate. See S. Rep. No. 94-369,
at 18, as reprinted in 1976 U.S.C.C.A.N. at 339 (“In the case
of allegations”); H.R. Rep. No. 94-838, at 33, as reprinted in
1976 U.S.C.C.A.N. at 365-66 (describing § 4213 as “giving
the Commission discretion to use either a summons or war-
rant when a condition of parole has alleged to have been vio-
lated”). Given the lack of any explanation of congressional
intent regarding the allegation clause specifically, Congress
might not have intended any substantive change from the
prior Acts. See H.R. Rep. No. 94-838, at 33, as reprinted in
1976 U.S.C.C.A.N. at 365-66; Hyser, 318 F.2d at 241 n.11;
see also 28 C.F.R. § 2.44 (continuing to require “satisfactory
evidence” of the alleged violation). But at the very least the
allegation clause clarifies that, in marked contrast to the impo-
sition of heightened safeguards for post-arrest revocation pro-
              SHERMAN v. U.S. PAROLE COMMISSION            11277
ceedings, Congress expressly kept to a minimum the
requirements for issuing a summons or warrant to ensure a
parolee’s appearance and intended to codify only those rights
prescribed by Morrissey and guaranteed under the Fourteenth
Amendment, not the Fourth Amendment.

                               4

   Finally, we are unpersuaded by Sherman’s argument that
we should construe § 4213 as incorporating the requirements
of the Warrant Clause in order to avoid raising serious doubts
as to its constitutionality. Although in Vargas-Amaya we so
applied the constitutional-doubt canon of statutory construc-
tion as to § 3583(i), we did so only as an alternative rationale
confirming our reading of the statute’s plain language.
Because our textual analysis mooted any potential constitu-
tional problems, we assumed arguendo that § 3583(i) was
fairly susceptible of two constructions and then employed the
canon of constitutional doubt to doubly reject the Govern-
ment’s reading. 389 F.3d at 906. The situation here is much
different, for our reading of § 4213’s plain text actually raises
constitutional issues. We therefore lack the luxury of engag-
ing in a hypothetical exercise in alternative rationales and
must determine whether the constitutional-doubt canon
applies at all. We conclude it does not.

   The canon of constitutional avoidance has no application
when a statute’s language is unambiguous and Congress’
intent is clear. As our preceding textual analysis reveals,
§ 4213 is susceptible of only one construction, which we
therefore must adopt despite its potential for raising a signifi-
cant constitutional question regarding the statute’s validity.
Almendarez-Torres v. United States, 

, 239
(1998). Although “one of the canon’s chief justifications is
that it allows the courts to avoid the decision of constitutional
questions,” avoidance cannot be an end in itself lest the canon
become something it is not — a method of resolving constitu-
tional questions by other means. Clark v. Martinez, 

1278         SHERMAN v. U.S. PAROLE COMMISSION
371, 381 (2005). The canon is merely a tool of statutory inter-
pretation, “not a license for the judiciary to rewrite language
enacted by the legislature” for “we cannot press statutory con-
struction to the point of disingenuous evasion even to avoid
a constitutional question.” Salinas v. United States, 

, 59-60 (1997) (internal quotation marks and citations omit-
ted). “The canon of constitutional avoidance comes into play
only when, after the application of ordinary textual analysis,
the statute is found to be susceptible of more than one con-
struction; and the canon functions as a means of choosing
between them.” Clark, 543 U.S. at 385. It “rest[s] on the rea-
sonable presumption that Congress did not intend the alterna-
tive which raises serious constitutional doubts” and “is thus a
means of giving effect to congressional intent, not of subvert-
ing it.” Id. at 381-82.

   [7] Moreover, our interpretation of § 4213 as excepting
administrative parole violator warrants from the Warrant
Clause of the Fourth Amendment is entirely consistent with
the presumption that Congress legislates in the light of consti-
tutional limitations. See Harris v. United States, 

,
556 (2002). As already discussed, the 1976 Act was passed
after the Anderson Court had analogized the rights of parole
violators with those of escaped prisoners, the Fourth and D.C.
Circuits had repeatedly rejected application of the Warrant
Clause to parole violator warrants, and the Morrissey Court
left such warrants alone in addressing the due process rights
of parole violators. Thus, “Congress would have had no rea-
son to believe that it was approaching the constitutional line
by following that instruction” and continuing to authorize the
issuance of parole violator warrants under substantially the
same procedures as the 1910 Act had originally allowed. Har-
ris, 536 U.S. at 556.

   [8] For all of the above reasons, we hold as a statutory mat-
ter that an administrative warrant issued by the Parole Com-
mission under 18 U.S.C. § 4213 for the retaking of an alleged
parole violator need not be supported by oath or affirmation.
              SHERMAN v. U.S. PAROLE COMMISSION           11279
Thus, Sherman has failed to establish any deprivation of his
statutory rights in support of his habeas petition.

                               B

   We now turn to the constitutional question implicated by
our statutory analysis. Pointing to the Fourth Amendment’s
prohibition that “no Warrants shall issue, but upon probable
cause, supported by Oath or affirmation,” Sherman contends
that sworn facts establishing probable cause are constitution-
ally required to support all warrants, even those issued by
administrative agencies pursuant to statute. Consequently, he
contends that his arrest and temporary detention on an
unsworn parole violator warrant issued by the Parole Com-
mission pursuant to 18 U.S.C. § 4213 is inconsistent with the
Warrant Clause and therefore unconstitutional. Cf. Payton v.
New York, 

, 574-75 (1980) (holding that New
York statutes authorizing warrantless entry into a private resi-
dence to make a routine felony arrest are inconsistent with the
Fourth Amendment). We disagree.

   No doubt, the once prevailing view that searches and sei-
zures of parolees present no Fourth Amendment issues has
been rejected in our modern jurisprudence. Latta v. Fitzharris,

, 248 (9th Cir. 1975) (en banc). But “[t]o hold
that the Fourth Amendment is applicable . . . is only to begin
the inquiry into the standards governing such intrusions.”
Skinner v. Ry. Labor Executives’ Ass’n, 

, 618-19
(1989).

   By now it is clear that parole searches and seizures must
“pass muster under the Fourth Amendment test of reasonable-
ness.” Latta, 521 F.2d at 248-49. Under the general Fourth
Amendment approach, we assess reasonableness by examin-
ing the totality of the circumstances and balancing the intru-
sion on the individual’s privacy against the promotion of
legitimate governmental interests. Samson, 126 S.Ct. at 2197.
“In most criminal cases, we strike this balance in favor of the
11280         SHERMAN v. U.S. PAROLE COMMISSION
procedures described by the Warrant Clause of the Fourth
Amendment” and therefore ordinarily require a search or sei-
zure to be “accomplished pursuant to a judicial warrant issued
upon probable cause.” Skinner, 489 U.S. at 619 (emphasis
added).

   Parole is different, however. “[R]evocation of parole is not
part of a criminal prosecution and thus the full panoply of
rights due a defendant in such a proceeding does not apply to
parole revocations.” Morrissey, 408 U.S. at 480. “Quite to the
contrary, the Court has recognized that those who have suf-
fered a lawful conviction are properly subject to a broad range
of restrictions that might infringe constitutional rights in free
society . . . .” United States v. Kincade, 

, 833
(9th Cir. 2004) (en banc) (internal quotation marks and brack-
ets omitted).

   Accordingly, in the parole context we have struck the
proper balance between the individual and public interests by
generally exempting parole searches and seizures from the
requirements of the Warrant Clause. In Latta we held that the
Fourth Amendment requires neither a warrant nor probable
cause before a parole officer may search a California parolee.
521 F.2d at 250 (en banc plurality); id. at 253 (Wright, J.,
concurring); id. (Choy, J., concurring). Moreover, we thought
it “indisputable, in view of the nature of parole and of the
parole agent’s responsibilities,” that even if a warrant were
constitutionally required “the showing necessary to obtain it
would have to be substantially different from probable cause
to avoid frustrating the purposes of parole.” Id. at 251. And
in United States v. Rabb, 

, 1324 (9th Cir. 1984),
we extended Latta to parole arrests. “Under the Latta analy-
sis, once a violation is established, the public interest in
apprehending parole violators outweighs the parolee’s privacy
interest,” such that “if a parole officer reasonably believes a
parolee is in violation of his parole, the officer may arrest the
parolee.” Id. Thus, as we later summarized: “Under California
and federal law, probable cause is not required to arrest a
              SHERMAN v. U.S. PAROLE COMMISSION           11281
parolee for a violation of parole. Warrantless arrests of parole
violators are also valid.” United States v. Butcher, 

, 814 (9th Cir. 1991).

   These principles apply equally to federal parolees like
Sherman. It is immaterial here that Latta, Rabb and Butcher
all involved California state parolees or that California law
may in some ways be stricter than federal law in terms of the
conditions placed on parolees. Compare Cal. Penal Code
Ann. § 3067(a) (West 2007) (requiring that state parolees
agree in writing to be subject to search or seizure at any time
“with or without a search warrant and with or without cause”)
with 28 C.F.R. § 2.44 (West 2007) (requiring “satisfactory
evidence” of a parole violation for the issuance of an adminis-
trative parole violator warrant). In Latta we considered the
Fourth Amendment rights of parolees without reference to
such jurisdiction-specific provisions and instead relied on
those characteristics of parole that are more universal — e.g.,
the nature, goals and purposes of parole, parolees’ unique
legal status and diminished expectation of privacy, and the
presence of long-standing statutory or judicial authority for
warrantless searches and seizures of parolees. 521 F.2d at
249-51. And Rabb’s extension of Latta to parole arrests was
based on the “same analytical framework” and an observation
that echoes the congressional intent underlying 18 U.S.C.
§ 4213: Given that a parolee “remains under legal custody,”
“a parole arrest [is] more like a mere transfer of the subject
from constructive custody into actual or physical custody,
rather than like an arrest of a private individual who is the
suspect of a crime.” Rabb, 752 F.2d at 1324 (internal quota-
tion marks omitted). Thus, while the jurisdiction-specific
aspects of California law may be a material factor in some cir-
cumstances, see, e.g., United States v. Lopez, 

,
1214 (9th Cir. 2007) (upholding a warrantless, suspicionless
search of a California parolee’s residence as reasonable in
light of the California parole-search statute and the parolee’s
conditions of release), nothing in the reasoning of Latta and
11282         SHERMAN v. U.S. PAROLE COMMISSION
its progeny would limit the precedential effect of those deci-
sions in the context of federal parole.

   [9] Because searches and seizures of parolees are generally
not subject to the requirements of the Warrant Clause, we
conclude that the Fourth Amendment does not require an
administrative parole violator warrant to be supported by oath
or affirmation. We therefore hold that petitioner’s arrest on a
unsworn parole violator warrant issued by the U.S. Parole
Commission pursuant to 18 U.S.C. § 4213 was not unconsti-
tutional under the Warrant Clause of the Fourth Amendment.

   Lest there be any confusion, our holding today is in keep-
ing with the fact that “[o]ur cases have not distinguished
between parolees, probationers, and supervised releasees for
Fourth Amendment purposes.” Kincade, 379 F.3d at 817 n.2.
The distinctions we have recognized between parole and
supervised release warrants are fundamentally statutory, not
constitutional. Vargas-Amaya stands for the relatively narrow
proposition that an ordinary judicial warrant that is statutorily
required for the arrest of a person on supervised release must
comply with the Warrant Clause of the Fourth Amendment in
order to extend the court’s jurisdiction under § 3583(i). See
Vargas-Amaya, 389 F.3d at 907 & n.5 (addressing “whether
a warrant for violation of the terms of release must comply
with the Warrant Clause,” given the fact that “by statute, a
[judicial] warrant was required to extend the court’s jurisdic-
tion”); cf. United States v. Murguia-Oliveros, 

,
955 (9th Cir. 2005) (holding that the court had jurisdiction to
revoke supervised release under § 3583(e)(3) despite the
releasee’s arrest on “an unsworn warrant”). We never consid-
ered the notion of an administrative warrant like that provided
in § 4213. See Vargas-Amaya, 389 F.3d at 904; see also id.
at 906 (discussing “all warrants” in terms of only “search”
and “arrest” warrants). And we expressly avoided the ques-
tion of whether a supervised releasee’s arrest must comply
with the Warrant Clause in the absence of a statute requiring
a judicial warrant. Id. at 907 n.5 (“we do not address whether
              SHERMAN v. U.S. PAROLE COMMISSION            11283
Vargas’ arrest was otherwise a valid warrantless arrest”); cf.
Latta, 521 F.2d at 250-51. That is the question we answer
today, albeit in the context of parole and given a statute that
requires “an administrative warrant, not a judicial warrant
within the scope of the Fourth Amendment.” Abel, 362 U.S.
at 232.

                               IV

   [10] We hold that neither 18 U.S.C. § 4213 nor the Fourth
Amendment require an oath or affirmation for the issuance of
a valid administrative warrant for the retaking of an alleged
parole violator. As petitioner alleges no other statutory or con-
stitutional defect in the warrant on which he was retaken and
held pending a preliminary hearing on revocation, we con-
clude his detention was not unlawful. The judgement of the
district court denying Sherman’s habeas petition challenging
his detention on an unsworn parole violator warrant is

  AFFIRMED.