Filed:   October 9, 2003

                    UNITED STATES COURT OF APPEALS

                        FOR THE FOURTH CIRCUIT


                             No. 02-4089
                             (CR-01-194)



United States of America,

                                                 Plaintiff - Appellee,

           versus


Betty Anne Osborne,

                                                Defendant - Appellant.



                              O R D E R



     The court amends its opinion filed September 25, 2003, as

follows:

     On page 5, second full paragraph, line 9; and page 6, second

full paragraph, line 11 -- “26 U.S.C.” is corrected to read “28

U.S.C.”

                                          For the Court - By Direction



                                           /s/ Patricia S. Connor
                                                    Clerk
                              PUBLISHED

            UNITED STATES COURT OF APPEALS

                  FOR THE FOURTH CIRCUIT
4444444444444444444444444444444444444444444444447
UNITED STATES OF AMERICA,
     Plaintiff-Appellee,

      v.                                                 No. 02-4089

BETTY ANNE OSBORNE,
     Defendant-Appellant.
4444444444444444444444444444444444444444444444448

            Appeal from the United States District Court
           for the District of South Carolina, at Florence.
                  C. Weston Houck, District Judge.
                             (CR-01-194)

                       Argued: May 9, 2003

                   Decided: September 25, 2003

    Before TRAXLER, KING, and GREGORY, Circuit Judges.

____________________________________________________________

Affirmed by published opinion. Judge Gregory wrote the opinion, in
which Judge Traxler and Judge King joined.

____________________________________________________________
                             COUNSEL

ARGUED: Robert Nathan Boorda, Columbia, South Carolina, for
Appellant. Thomas Ernest Booth, UNITED STATES DEPART-
MENT OF JUSTICE, Washington, D.C., for Appellee. ON BRIEF:
J. Strom Thurmond, Jr., United States Attorney, Rose Mary Parham,
Assistant United States Attorney, UNITED STATES DEPART-
MENT OF JUSTICE, Washington, D.C., for Appellee.

____________________________________________________________
                               OPINION

GREGORY, Circuit Judge:

   On July 26, 2001, Betty Anne Osborne ("Osborne") entered a
guilty plea before a magistrate judge to one count of conspiring to
possess with intent to distribute cocaine and cocaine base. On appeal,
Osborne challenges: 1) the quantity of drugs attributed to her for sen-
tencing purposes; and 2) the district judge's failure to conduct de
novo review of the Rule 11 proceedings conducted by the magistrate
judge. As explained below, the court did not err in determining the
quantity of drugs attributable to Osborne, and a district judge is not
required, absent a defendant's request, to review de novo the Rule 11
proceedings conducted by a magistrate judge. Thus, we affirm
Osborne's conviction and sentence.1
____________________________________________________________
    1
      Osborne also challenges her 188-month sentence. We note that there
is a discrepancy between the 188-month sentence entered in the written
criminal judgment and the sentence of 180 months that the district judge
pronounced orally at the sentencing hearing. It is normally the rule that
where a conflict exists between an orally pronounced sentence and the
written judgment, the oral sentence will control. See, e.g., United States
v. Morse, 

, 29 n.1 (4th Cir. 1965) ("To the extent of any con-
flict between [a] written order and [an] oral sentence, the latter is control-
ling."); United States v. Daddino, 

, 266 & n.5 (citing cases).
However, in this instance, the entry of a sentence of 180 months would
fall below the minimum guideline sentence of 188 months. Because the
sentencing transcript indicates that the district court adopted the guide-
line sentencing range and recognized that there was no basis for a down-
ward departure, we view the 180-month orally pronounced sentence as
ambiguous. In light of this ambiguity, we shall look to the written crimi-
nal judgment as evidence of the sentencing court's intent. See United
States v. Brown, 47 Fed. Appx. 305, 314-315 (6th Cir. 2002) (unpub-
lished) (finding oral pronouncement was ambiguous and looking to writ-
ten criminal judgment to resolve ambiguity where the court's oral
pronouncement would have placed the sentence below the guideline
range); United States v. McWilliams, 1 Fed. Appx. 339, 344 (6th Cir.
2001) (unpublished) (same). From the written sentence, and the district
judge's explicitly stated intent to follow the guidelines, we conclude that
the district judge intended to sentence Osborne to 188 months and there-
fore affirm her written sentence.

                                    2
                                  I.

   During the execution of a search warrant, government agents dis-
covered illegal drugs in Osborne's home. On Osborne's person, the
agents found four grams of cocaine base. Further, Osborne's co-
defendant, for whom she "cooked" cocaine into crack for the distribu-
tion thereof, was found to be in possession of more than six grams of
cocaine base.

   Osborne pleaded guilty to one count of conspiracy to possess with
the intent to distribute five grams or more but less than fifty grams
of cocaine base, in violation of 21 U.S.C. § 846. Osborne waived her
right to enter a guilty plea before a district judge, and consented to
have a magistrate judge accept her plea. The magistrate judge con-
ducted a plea hearing pursuant to Fed. R. Crim. P. 11, in which he
determined that there was a factual basis for Osborne's conviction.
Upon accepting her guilty plea, the magistrate judge advised Osborne:

         [T]he district judge retains control and jurisdiction over your
         case, and that the matter of acceptance or rejection of your
         plea agreement and the matter of sentencing will be left to
         the district judge. Any perceived deficiencies in this hearing
         or any other matters that you may have will be taken up with
         the district judge at the time of sentencing.

Finally, the magistrate judge informed Osborne that, at sentencing,
the district court would rely upon a written presentence report
("PSR"), to which her counsel would have an opportunity to object.

    At the sentencing hearing, the district judge invited Osborne to
object to or comment upon the PSR. Osborne declined, and the dis-
trict judge adopted the statements contained in the PSR as its findings
of fact for sentencing. The PSR reflected Osborne's admission of
responsibility for the charged offense, and it recommended the related
sentencing adjustment. Based upon the PSR, the district judge found
that Osborne had a total offense level of 31, with a criminal history
category of VI, yielding a sentencing range of 188 to 235 months. The
district judge orally sentenced Osborne to 180 months. However, the
district judge's written order entering judgment reflected a sentence
of 188 months. At no time prior to this appeal did Osborne challenge

                                  3
the quantity of drugs attributed to her for sentencing purposes, nor did
she object to the magistrate judge's authority to conduct the Rule 11
proceedings in her case.

                                  II.

    Because this is the first time that Osborne has challenged the quan-
tity of drugs attributed to her for sentencing purposes, we review this
issue only for plain error. United States v. Olano, 

, 732
(1993). In order to prevail under this standard, a defendant must
establish that an error occurred, that it was plain, and that it affected
her substantial rights. 

if a defendant can make such
a showing, a reviewing court should exercise its discretion to correct
such error only when it seriously affects the fairness, integrity or pub-
lic reputation of judicial proceedings. 

never requested that the district judge review
the magistrate judge's authority to conduct Rule 11 proceedings, and
she did not initially raise this issue on appeal. Sua sponte, we directed
the parties to file supplemental briefs on the issue. We did so because
we have an independent duty to assess jurisdictional issues, and we
deem it appropriate in this case to consider the scope of a magistrate
judge's authority to conduct Rule 11 proceedings. See United States
v. Dees, 

, 263 (5th Cir. 1997). Because this issue was not
raised below, however, we review it for plain error.2 United States v.
Torres, 

, 794 (8th Cir. 2001).

                                  III.

   This appeal presents two issues: 1) whether the district court cor-
rectly calculated the quantity of drugs attributable to Osborne for sen-
tencing purposes; and 2) whether the district court erred in failing to
review de novo the Rule 11 proceedings conducted by the magistrate
judge.
____________________________________________________________
   2
     We note that the Tenth Circuit has held that it will apply the plain
error rule "less rigidly" when reviewing constitutional issues not raised
during trial. United States v. Ciapponi, 

, 1249-50 (10th Cir.
1996). In deciding this case, however, we find it unnecessary to deter-
mine the appropriateness of such a rule.

                                   4
                                  A.

    We first assess whether the district court correctly calculated the
quantity of drugs attributable to Osborne for sentencing purposes.
This issue is easily disposed of pursuant to standard principles of
derivative liability. A conspirator may be held accountable for all
quantities of drugs attributable to the conspiracy so long as it was rea-
sonably foreseeable that the drugs would be involved in the conspir-
acy and that the drugs were possessed within the scope of the
conspiratorial agreement. See United States v. Gilliam, 

, 1013 (4th Cir. 1993). Osborne admitted to processing cocaine
base into crack cocaine for her co-defendant's distribution operation.
At the time of her arrest, over ten grams of crack cocaine were found
in her residence — either in her possession or in her co-defendant's
possession. Under these circumstances, the district court did not err
in sentencing Osborne for possession of five or more grams of crack
cocaine.

                                  B.

    In order to assess whether the district judge erred in accepting
Osborne's plea without conducting de novo review thereof, we must
first consider whether the Federal Magistrates Act, 28 U.S.C. §§ 631-
639 (1988) (the "Act"), authorizes a magistrate judge to preside over
Rule 11 proceedings. Second, we must determine whether Article III
of the Constitution requires a district judge to conduct de novo review
of such proceedings, irrespective of a defendant's request for such
review. As all of our sister circuits have determined, we conclude that
the Act, pursuant to its "additional duties" clause, 28 U.S.C.
§ 636(b)(3), authorizes magistrate judges to conduct Rule 11 proceed-
ings. Further, we hold that a district judge need not review such pro-
ceedings de novo unless a defendant requests such review.3
____________________________________________________________
   3
     We note that only two of our sister circuits, the Ninth Circuit in
United States v. Reyna-Tapia, 

(9th Cir. 2003) (en banc),
petition for cert. filed, No. 03-5303 (U.S. July 1, 2003), and the Tenth
Circuit in United States v. Ciapponi, 

(10th Cir. 1996), have
directly addressed the question of whether de novo review is required
regardless of a defendant's request. Both of these circuits concluded, as
we do today, that such review is required only upon request. Reyna-

; 

.

                                   5
                      1. Statutory Authorization

    Every circuit to have considered whether the Act authorizes a mag-
istrate judge to conduct Rule 11 proceedings has held that the Act per-
mits such a delegation. See 

; United
States v. Torres, 

, 795-97 (8th Cir. 2001); United States
v. Dees, 

, 264-67 (5th Cir. 1997); United States v. Ciap-
poni, 

, 1250-52 (10th Cir. 1996); United States v. Wil-
liams, 

, 632-35 (2d Cir. 1994). In reaching this
conclusion, these courts have relied upon, first, the language in the
Act itself, and second, the Supreme Court's decision in Peretz v.
United States, 

(1991), which addressed whether magis-
trate judges may be assigned the task of supervising voir dire pro-
ceedings. Like our sister circuits, we conclude that the Act authorizes
a magistrate judge to conduct Rule 11 plea proceedings.

    In assessing the statutory question, we begin with the Supreme
Court's decision in Peretz. There, the Court held that a magistrate
judge may, if the defendant so consents, conduct voir dire in a crimi-
nal case. 

On the statutory issue, the Court looked to the
Act itself to determine whether a magistrate judge is authorized to
preside over voir dire proceedings. Although the Act does not
expressly authorize magistrate judges to conduct voir dire proceed-
ings as a delegable duty, see 28 U.S.C. § 636(b)(1)(A)-(B), the "addi-
tional duties" clause does provide that "[a] magistrate may be
assigned such additional duties as are not inconsistent with the Con-
stitution and laws of the United States." 28 U.S.C. § 636(b)(3). In an
earlier decision, Gomez v. United States, 

, 876 (1989),
the Supreme Court concluded that, when a defendant objected, the
"additional duties" clause did not authorize magistrate judges to
supervise voir dire proceedings. As the Court discussed in Peretz, the
Gomez Court was concerned that an interpretation of the "additional
duties" clause to allow delegation of voir dire proceedings under such
circumstances would raise constitutional concerns regarding whether
a defendant has a "constitutional right to demand that an Article III
judge preside at every critical stage of a felony trial." 

. Under these circumstances, the Court in Gomez declined to
construe the Act to authorize a magistrate judge to conduct voir dire
in a situation where the defendant objected. 

-
76.

                                   6
    By contrast, in Peretz, where the defendant agreed to allow the
magistrate judge to preside over the voir dire proceedings, the Court
concluded that the Act authorizes such a 

.
Because of the defendant's consent, the Court was not faced with the
constitutional concerns that troubled the Court in Gomez. 

Hence, the Peretz Court was free to examine the history and purpose
of the Act to determine whether supervision of voir dire proceedings
was an additional duty that could properly be delegated to a magis-
trate judge. The Court read the "additional duties" clause in light of
legislative history supporting "`innovative experimentations' in the
use of magistrates to improve the efficient administration of the
courts' dockets," and found "[t]he Act evidences a congressional
belief that magistrates are well qualified to handle matters of similar
importance to jury selection but conditions their authority to accept
such responsibilities on the consent of the parties." 

(quoting H.R. Rep. No. 94-1609, at 12 (1976)). The Court defined
"additional duties" to include only those duties that "bear some rela-
tion to the specified duties that the statute assigned to magistrates."

(internal quotation omitted). Applying this test, the Court
concluded that the supervision of voir dire proceedings was compara-
ble to expressly delegable duties, and it therefore held that the "addi-
tional duties" clause authorizes a magistrate judge to perform this
function — as long as the defendant consents. 

   Applying Peretz's approach to "additional duties," our sister cir-
cuits have uniformly concluded that the Act authorizes a magistrate
judge to preside over Rule 11 proceedings. For example, the Second
Circuit, in United States v. Williams, concluded that magistrate judges
possess the statutory authority to conduct Rule 11 

. In that situation, the court noted that Rule 11 itself
largely dictates the steps of the plea colloquy. 

Accordingly,
the court concluded that the supervision of Rule 11 proceedings is
less complex, and it involves less discretion, than the duties the Act
expressly authorizes a magistrate judge to perform. 

(not-
ing that § 636(b)(1)(A) and (B) authorize magistrate judges to hear
and determine certain pre-trial matters, conduct evidentiary hearings,
and submit recommended findings of fact on various matters, includ-
ing habeas corpus petitions). Finally, the court discussed how the
Act's legislative history supports an expansive reading of delegable
duties. In particular, the court noted that the Act clearly envisions that

                                   7
magistrate judges will perform functions that extend beyond pre-trial
matters. 

(citing H.R. Rep. No. 94-1609, at 12 (1976)). In
light of these factors, the court concluded that the "additional duties"
clause should be read to allow a magistrate judge to preside over Rule
11 proceedings. 

    In United States v. Ciapponi, the Tenth Circuit likewise held that
the Act authorizes a magistrate judge to conduct Rule 11 

. There, the court discussed the Supreme Court's deci-
sions in Peretz and Gomez, and the Second Circuit's decision in Wil-
liams. 

While the court in Ciapponi did not draw a
clear distinction between statutory and constitutional inquiries, it did
make clear that, on the statutory issue, it was holding that "with a
defendant's express consent, the broad residuary`additional duties'
clause of the Magistrates Act authorizes a magistrate judge to conduct
a Rule 11 felony plea proceeding." 

Further, the court
emphasized that the availability of de novo review, as opposed to the
exercise thereof, was a significant factor in upholding the delegation.

("[T]o the extent that defendant challenges the delega-
tion . . . because section 636(b)(3) contains no express procedures for
de novo review, the Supreme Court rejected this argument in Peretz.
The Court held, to the extent de novo review is required . . . it need
not be exercised unless requested by the parties." (internal quotation
omitted) (emphasis added)).

    Similarly, in United States v. Dees, the Fifth Circuit concluded that
a magistrate judge has the statutory authority, pursuant to the "addi-
tional duties" clause of the Act, to preside over Rule 11 

. In addition to discussing the factors that the Sec-
ond Circuit had detailed in Williams, the Fifth Circuit looked to one
of its earlier decisions, United States v. Rojas, 

, 42 (5th
Cir. 1990), in which it had held that the Act, pursuant to § 636(b)(1),
authorizes a magistrate judge to conduct an evidentiary hearing to
assess the voluntariness of a guilty plea. 

.
Although Rojas involved an express delegation under § 636(b)(1) of
the Act, the court in Dees found that "plea proceedings bear a close
relationship to the evidentiary hearing we considered in Rojas." 

In both situations, the district judge retained, in the form of de
novo review of a magistrate judge's decisions, the ultimate supervi-
sory authority over the proceedings. Further, the court noted that the

                                   8
Rule 11 plea colloquy involved "much more of a ministerial function"
than the evidentiary hearing involved in Rojas. 

Accord-
ingly, the Fifth Circuit joined its sister circuits in construing the Act
to permit delegation of the Rule 11 plea colloquy.

    Finally, the Ninth Circuit, sitting en banc, in United States v.
Reyna-Tapia, recently decided that the Act authorizes magistrate
judges to conduct Rule 11 

. The court
recognized that "the taking of guilty pleas is not listed among the
duties that can be designated to magistrate judges," 

went on
to analyze whether the "additional duties" clause applied. As other
courts had done, the Ninth Circuit decided, in accordance with the
Supreme Court's interpretation of the "additional duties" clause in
Peretz, that the supervision of Rule 11 proceedings is similar to duties
that magistrate judges are expressly authorized to perform. 

court joined "every other circuit examining the ques-
tion in holding that the taking of a guilty plea by a magistrate judge,
with the litigants' consent, qualifies as an additional duty under
§ 636(b)(3)." 

sister circuits, we look to the approach developed by the
Court in Peretz. The supervision of Rule 11 plea proceedings, while
obviously requiring care and discretion to ensure that guilty pleas rest
upon a firm factual basis, hardly dwells nigh the outlands of magistra-
ture.4 Applying the "additional duties" test developed in Peretz, we
____________________________________________________________
    4
      By contrast, in United States v. Bryson, 

, 725-26 (4th
Cir. 1992), we declined to adopt a reading of "additional duties" that
would permit a magistrate judge, without the defendant's consent, to dis-
miss a habeas corpus petition under 28 U.S.C. § 2255. In reaching this
"quite narrow" holding, 

we relied upon Peretz's discussion of
the centrality of consent in defining the scope of permissible "additional
duties." 

("[T]he duties that a magistrate may perform over the
parties' objection are generally subsidiary matters . . . . However, with
the parties' consent, a district judge may delegate to a magistrate supervi-
sion of entire civil and misdemeanor trials."). Hence, while we recog-
nized that allowing the magistrate judge to perform this function over the
parties' objections might further the efficiency purposes of the Act, 

we concluded that such an interpretation would run afoul of the
constitutional concerns articulated in Peretz and Gomez. We did, how-
ever, make clear that we might have decided the case differently if the
defendant had properly waived his right to have an Article III judge adju-
dicate his habeas petition. 

                                   9
observe that allowing a magistrate judge to supervise voir dire pro-
ceedings in a felony trial implicates far greater discretion than the del-
egation of Rule 11 responsibilities. At the same time, we note that,
because both processes are fraught with constitutional concerns, a
defendant must clearly waive his right to have such proceedings con-
ducted by an Article III judge. See 

. As other
circuits have concluded, a magistrate judge capable of supervising an
entire civil or criminal misdemeanor trial may surely perform the plea
colloquy so clearly delineated in Rule 11. Additionally, as the en banc
Ninth Circuit noted, a Rule 11 proceeding implicates issues such as
voluntariness and the factual basis for guilt — issues that a magistrate
judge may be asked to resolve pursuant to the duties outlined in
§ 636(b)(1)(a) of the Act. See 

. Finally,
it is clear that this reading of the "additional duties" clause furthers
the basic purpose of the Act and permits the types of experimentation
and resource utilization envisioned by Congress.

               2. Constitutionality and De Novo Review

    Having determined that the Act's "additional duties" clause autho-
rizes a magistrate judge to conduct Rule 11 proceedings, we must
assess whether this statutory grant is consistent with Article III of the
Constitution.5 In resolving this question affirmatively with respect to
voir dire, the Supreme Court in Peretz examined two separate consti-
tutional issues: 1) a defendant's right to the presence of an Article III
judge at critical phases of trial; and 2) the structural integrity of the

. Noting that a criminal defendant may
waive even his most basic procedural rights, the Supreme Court con-
cluded that "the Constitution . . . gives no assistance to a defendant
who fails to demand the presence of an Article III judge at the selec-
tion of his jury." 

If a defendant may waive his right to have
____________________________________________________________
   5
     Section 1 of Article III vests the judicial power in "one supreme
Court, and in such inferior Courts as the Congress may from time to time
ordain and establish." U.S. Const. Art. III, § 1. The Supreme Court has
interpreted this provision to limit Congress's ability to vest judicial
authority in non-Article III judges. See, e.g., Northern Pipeline Constr.
Co. v. Marathon Pipe Line Co., 

, 58-60 (1982) (discussing
the importance of a Judiciary that is independent from the control of the
Executive and Legislative branches).

                                   10
an Article III judge conduct voir dire, we see no reason why he
should not be permitted to waive his right to have an Article III judge
supervise his plea colloquy.6

    Second, turning to consider whether the delegation implicates the
structural integrity of the judiciary, the Supreme Court discussed its
earlier approval, in United States v. Raddatz, 

(1980), of
a magistrate judge's authority to decide a motion to suppress:

         When a matter is referred, the judge may freely reject the
         magistrate's recommendation. He may rehear the evidence
         in whole or in part. He may call for additional findings or
         otherwise recommit the matter to the magistrate with
         instructions. Moreover, the magistrate himself is subject to
         the Art. III judge's control. Magistrates are appointed by
         district judges, and subject to removal by them.

(quoting 

(Blackmun,
J., concurring) (internal quotation and citations omitted)). Thus, what
the Court found dispositive in its structural analysis was the preserva-
tion of the judiciary's power to review the activity of a non-Article
III judge's work. 

(describing district judge's supervision of
magistrate judge as means of preventing congressional transfers of
jurisdiction for "purpose of emasculating constitutional courts" (inter-
nal quotation omitted)). Turning to the precise nature of this power
to supervise, the Supreme Court noted that Raddatz turned upon
§ 636(b)(1), which contained an express provision for de novo review
by a district judge. Nonetheless, despite the absence of a similar pro-
vision in the "additional duties" clause, the Peretz Court adopted the
approach articulated in Raddatz, where such review "need not be
exercised unless requested by the parties." 

(emphasis
added) (internal quotation omitted). Hence, the Court held that it was
the availability of review, upon request by the parties, rather than a
required performance thereof, that safeguarded the integrity of the
federal judiciary. 

conclusion follows logically considering
that the Court's concern in the second part of its constitutional analy-
____________________________________________________________
   6
     Of course, a challenge to the waiver itself, upon the appropriate show-
ing of error, may be raised after a plea has been entered — a factual
predicate not before us today.

                                  11
sis turned upon the structural power of the Article III court rather than
the defendant's liberties.7

   Considering the matter at hand, we again note that there is little rel-
evant precedent regarding the constitutionality of "additional duties"
clause delegations in this Circuit. In particular, we have never consid-
ered whether Rule 11 proceedings may be delegated to a magistrate
judge.8 Under Peretz, we are bound to decide whether the availability
of de novo review suffices here to safeguard the integrity of constitu-
tional courts. Osborne could have requested review by the district
judge of her Rule 11 plea proceeding. However, she did not. Had the
____________________________________________________________
   7
     The power of the district judge to review a magistrate judge's perfor-
mance of delegated duties will help to assure protection of the defen-
dant's constitutional liberties.
    8
      Unfortunately, one may read the opinions of our sister circuits on this
issue and come away wanting some degree of clarification. In Torres, for
example, the Eighth Circuit wrote that the Second (United States v. Wil-
liams, 

(2d Cir. 1994)), Fifth (United States v. Dees, 

(5th Cir. 1997)), and Tenth (United States v. Ciapponi, 

(10th Cir. 1996)) Circuits had concluded that a magistrate judge may pre-
side over Rule 11 proceedings, "so long as the district court exercises de
novo review of the magistrate judge's 

. Con-
trary to this interpretation, no circuit has held that de novo review is
required absent a defendant's request. The Tenth Circuit in Ciapponi
expressly rejected such a requirement, holding instead that de novo
review is necessary only upon 

. Furthermore,
the Second Circuit was not squarely presented with the issue in Williams
because the district court had in fact conducted such review. Neverthe-
less, to the extent it considered the issue at all, the court emphasized that
it was the availability of de novo review that made the delegation consis-
tent with Article 

("[T]here should be no concern that
the use of a magistrate judge to allocute a defendant accused of a felony
will tend to devitalize Article III courts. A district judge may readily read
the transcript of the allocution for infirmities, if any, and may re-
administer the allocution if it is thought necessary." (emphasis added)
(citation omitted)). Finally, the Fifth Circuit in Dees based its finding of
Article III constitutionality upon the availability of de novo review,
rather than the exercise 

n.7 ("Even though the
Magistrates Act does not expressly provide for de novo review of plea
proceedings, the only constitutional requirement is that it be available if
the parties so request." (emphasis added)).

                                  12
district judge denied such a request, we would have before us a funda-
mentally different case. Hence, like the Ninth and Tenth Circuits,
both of which held that de novo review is not required where the
defendant clearly consents to entering a plea before a magistrate judge
and raises no objection to the Rule 11 plea proceeding, we hold that
unless the defendant requests such review or objects to some aspect
of the magistrate judge's plea colloquy, a district judge is not bound
to conduct de novo review. That is, there is no entitlement to de novo
review absent a request therefor.

                                 IV.

   Finding no error in the quantity of drugs upon which Osborne's
sentence was based, and finding no obligation of the district court to
review the magistrate's Rule 11 colloquy, we hereby

                                                             AFFIRM.

                                  13