United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
      ___________

      No. 05-1245
      ___________

United States of America,              *
                                       *
            Appellee,                  *
                                       *
      v.                               *
                                       *
Arthur Sanchez,                        *
                                       *
            Appellant.                 *

      ___________
                                           Appeals from the United States
      No. 05-1345                          District Court for the District of
      ___________                          Minnesota

United States of America,              *
                                       *
            Appellee,                  *
                                       *             [PUBLISHED]
      v.                               *
                                       *
Carlos Villa, also known as Santiago   *
German Sanchez,                        *
                                       *
            Appellant.                 *

                                  ___________

                             Submitted: September 13, 2005
                                Filed: November 16, 2005
                                 ___________
Before ARNOLD, HANSEN, and MURPHY, Circuit Judges.
                           ___________

PER CURIAM.

       Carlos Villa appeals, challenging the reasonableness of his 155-month sentence
for conspiring to distribute more than 500 grams of a methamphetamine mixture, see
21 U.S.C. §§ 841 (b)(1)(A), 846. His co-defendant, Arthur Sanchez, appeals his
conviction for the same crime and for aiding and abetting another in possessing more
than 500 grams of a methamphetamine mixture with the intent to distribute it, see
18 U.S.C. § 2; 21 U.S.C. § 841 (a)(1), (b)(1)(A). He maintains that he was deprived
of his due process right to a fair trial and to compulsory process. We affirm the
judgments of the district court1 in all respects.

                                           I.
       Mr. Villa pleaded guilty to the conspiracy count and testified in Mr. Sanchez's
trial pursuant to a plea agreement. Another participant in the operation, Hilario
Rodriguez, also pleaded guilty and cooperated with the government. Shortly after the
Supreme Court ruled that the United States Sentencing Guidelines are advisory only,
see United States v. Booker, 

, 764-65 (2005), the district court
sentenced Mr. Villa to 155 months in prison. Mr. Villa contends that his sentence is
unreasonable, given proper consideration of the relevant matters and compared with
Mr. Rodriguez's 70-month sentence.

      We review the reasonableness of a sentence for an abuse of discretion. See
United States v. Dalton, 

, 1032 (8th Cir. 2005). A sentence is
reasonable and not an abuse of discretion if the sentencing court considers the matters


      1
       The Honorable Donovan W. Frank, United States District Judge for the
District of Minnesota.
                                         -2-
contained in 18 U.S.C. §3553(a), does not consider inappropriate matters, and makes
no clear error of judgment. See United States v. Haack, 

, 1004 (8th Cir.
2005), cert. denied, 

(2005). The record reflects that the district judge
weighed the sentencing guidelines range (235-293 months), the assistance that
Mr. Villa provided to the government, see U.S.S.G. 5K1.1, the degree to which courts
in the district generally reduced a sentence for substantial assistance, Mr. Villa's role
in the conspiracy, and other matters set out in §3553(a). The record provides no basis
for concluding that the district judge abused his discretion in sentencing Mr. Villa to
155 months, which is about one-third less than the low end of the guidelines range.
In this case, the fact that Mr. Rodriguez received a lesser sentence is wholly irrelevant
to the question of whether Mr. Villa's sentence was unreasonable.

                                          II.
       Mr. Sanchez's challenge to the government's conduct with respect to its
confidential informant is similarly infirm. Although Mr. Sanchez believed that
Margaret Romero, who had previously rented a room in the house in which he was
living, was the "confidential informant" relied on in an affidavit of a Drug
Enforcement Administration special agent to support a search warrant request, the
government did not confirm his suspicion until the Wednesday before trial.
Mr. Sanchez argues that because the government refused "timely to produce"
Ms. Romero, he was unable to subpoena her for trial and was thereby denied his right
to a fair trial and to compulsory process. Roviaro v. United States, 

, 60-
61 (1957).

       The government initially resisted Mr. Sanchez's motion to disclose or produce
the informant but agreed after a hearing to make her available the week before trial.
Eight days before trial, the government announced that it would not produce her after




                                          -3-
all because, inter alia, it had decided not to call her as a witness. A magistrate judge2
then ordered the government to "disclose [the informant's] name and address to
defendant Sanchez or, in the alternative, produce the informant for interview" no later
than one week before trial because she was "an active participant in and witness to
the events underlying the offenses charged." The judge added in a footnote that the
government should produce the informant for Mr. Sanchez "in lieu of" providing her
address if it was aware that Mr. Sanchez "may encounter difficulty" in locating her.
Six days before trial, the government identified the informant as Ms. Romero and
provided her last known address, but neither defense counsel nor the United States
Marshals could find her. Although Ms. Romero did not testify at trial, the district
court granted Mr. Sanchez's counsel's request to present to the jury (through cross-
examination of the DEA agent) hearsay statements of Ms. Romero that appeared in
the agent's affidavit. In these statements, which Mr. Sanchez's counsel described as
being in "his [client's] favor," Ms. Romero inculpated herself in the drug conspiracy
without mentioning Mr. Sanchez.

       Under 

, the government has an obligation to disclose
the identity of a confidential informant "[w]here the disclosure of an informer's
identity, or of the contents of his communication, is relevant and helpful to the
defense of an accused, or is essential to a fair determination of a cause." We have
elaborated on the circumstances in which this duty applies, holding that if the
informant is an active participant in the conduct charged, the informant's identity is
"almost always" material and thus the government must "make every reasonable
effort to have the informant made available to the defendant." United States v.
Barnes, 

, 779-80 (8th Cir. 1973); cf. 

n.15.
"[S]pecial problems associated with locating and protecting informants" may
sometimes require the government to produce an informant, even if the defendant


      2
       The Honorable Jaynie S. Mayerson, United States Magistrate Judge for the
District of Minnesota.
                                          -4-
already knows the informant's identity, see United States v. Padilla, 

,
376-77 (8th Cir. 1989), cert. denied, 

(1989).

       Here, however, the government provided the name and last known address of
the informant to Mr. Sanchez, and counsel for the government stated during trial that
the government's attempts to find her had been unsuccessful. The defendant did not
seek a hearing to determine whether the government had made "reasonable effort[s]"
to locate Ms. Romero, see 

, or otherwise complied with its
Roviaro duty. Mr. Sanchez asserts that he objected at trial to the government's
conduct, but that those objections were not recorded. He nonetheless has not asked
for the record to be supplemented under Fed. R. App. P. 10(e).

       Absent a record preserving the Roviaro issue, we apply the plain error standard.
Fed. R. Crim. P. 52(b); cf. United States v. Bullard, 

, 767 (1st Cir. 1994),
cert. denied, 

(1995). Because it is not obvious on this record that the
government violated any duty that it may have had under Roviaro, we are obligated
to affirm the conviction.

      Mr. Sanchez's other assignments of error are without merit.

      For the reasons stated, we affirm the judgments.
                      ______________________________




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