FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                        No. 08-50062
                Plaintiff-Appellee,                 D.C. No.
               v.                                CR-06-00545-
UIESE MAUSALI,                                      GHK-3
             Defendant-Appellant.
                                                  OPINION

         Appeal from the United States District Court
            for the Central District of California
          George H. King, District Judge, Presiding

                 Submitted December 11, 2009*
                     Pasadena, California

                      Filed January 11, 2010

  Before: Cynthia Holcomb Hall and Barry G. Silverman,
 Circuit Judges, and Suzanne B. Conlon,** District Judge.

                  Opinion by Judge Silverman




   *The panel unanimously finds this case suitable for decision without
oral argument. See Fed. R. App. P. 34(a)(2).
   **The Honorable Suzanne B. Conlon, United States District Judge for
the Northern District of Illinois, sitting by designation.

                                 721
                   UNITED STATES v. MAUSALI                 723




                         COUNSEL

Cristina Gabrielidis Lechman, Lechman & Lechman, San
Diego, California, for the appellant.

Thomas P. O’Brien, United States Attorney; Christine C.
Ewell, Assistant United States Attorney; Rodrigo A. Castro-
Silva, Assistant United States Attorney; and Joseph N. Akro-
tirianakis, Assistant United States Attorney; Los Angeles,
California, for the appellee.


                          OPINION

SILVERMAN, Circuit Judge:

  We hold today, as have the Second, Third, and Eighth Cir-
cuits, that a defendant waives his claim of outrageous govern-
ment conduct of which he is aware if he fails to assert it in
a pretrial motion to dismiss. In this case, the defendant failed
to raise outrageous government conduct before the district
court prior to trial, during trial, or even after trial, despite
knowing the facts supposedly supporting his claim months
before trial began. Accordingly, he has waived this issue for
purposes of appeal. We affirm.

I.   Background

  In May 2006, Special Agent John Carr of the Bureau of
Alcohol, Tobacco, and Firearms, asked a confidential infor-
724                UNITED STATES v. MAUSALI
mant to let him know if the informant came across any crews
interested in committing a home invasion robbery. Carr hoped
to infiltrate an existing robbery crew by portraying himself as
a drug courier who intended to pay off thousands of dollars
in gambling debts by fencing drugs stolen from his employ-
er’s stash house. Within a few weeks, the informant put Carr
in touch with Diego Osuna-Sanchez, who told Carr that he
had an armed and experienced robbery crew interested in
working with him. The crew consisted of Osuna-Sanchez,
Juan Okamoto, Mokey Mose, and the defendant, Uiese Maus-
ali.

   Over the course of the next month, Carr met several times
with Osuna-Sanchez, Okamoto, Mose, and Defendant to work
out the details of the robbery; each member of the crew par-
ticipated in the planning. On the morning of June 23, 2006,
Okamoto, Mose, and Defendant met up with Carr at a ware-
house parking lot to hash out the final details of the job on
their way to the stash house. Before Okamoto, Mose, and
Defendant could leave, however, ATF agents emerged and
took them into custody. Agents found a loaded sawed-off
shotgun, a bulletproof vest, and a roll of duct tape inside
Defendant’s car. Defendant later admitted in a post-arrest
interview with local police that he had been involved in the
plan to rob the stash house.

   A grand jury returned an indictment against Osuna-
Sanchez, Okamoto, Mose, and Defendant, charging Defen-
dant with: (1) conspiracy to distribute at least five kilograms
of cocaine, in violation of 21 U.S.C. §§ 841(b)(1)(A)(ii) and
846; (2) conspiracy to interfere with interstate commerce by
robbery, in violation of 18 U.S.C. § 1951; (3) possessing a
firearm in furtherance of a drug trafficking crime, in violation
of 18 U.S.C. § 924(c); and (4) felon in possession of a fire-
arm, in violation of 18 U.S.C. § 922(g)(1). Both Okamoto and
Osuna-Sanchez pled guilty; Mose and Defendant proceeded
to trial.
                   UNITED STATES v. MAUSALI                   725
   Prior to trial, Mose moved to sever his and Defendant’s tri-
als, citing Bruton v. United States, 

(1968), and
generally claiming the possibility that Mose and Defendant
would pursue mutually antagonistic defenses; Defendant nei-
ther joined this motion nor filed his own. The district court
denied Mose’s severance motion. After the Government pre-
sented its case-in-chief, both Mose and Defendant challenged
the sufficiency of the evidence and moved for acquittal, pur-
suant to Fed. R. Crim. P. 29. The district court denied both
motions. Mose did not renew his severance motion.

   During jury deliberations, the foreperson sent a note to the
judge indicating that one of the jurors felt he could no longer
remain impartial. With the consent of all parties, the district
court questioned the foreperson outside the presence of the
other jurors to determine the identity of the problematic juror,
and then questioned that juror, also outside the presence of the
other jurors; the juror explained that he could not fairly decide
the case solely on the basis of the evidence and the court’s
instructions. The parties agreed and the district court deter-
mined that there was good cause to excuse the juror. At the
Defendant’s request, the district court also asked the juror
whether he had discussed the basis of his inability to remain
impartial with the other jurors, and the juror said he had not.
Defendant did not ask the district court either to question the
rest of the jury panel or to grant him a mistrial. Ultimately, the
district court replaced the juror in question with an alternate,
and Defendant declined the district court’s invitation to seek
additional relief beyond replacement of the juror and the
renewal of deliberations. On January 22, 2007, the jury found
Mose and Defendant guilty of all charges.

   A presentence investigation report was prepared, which
stated that Defendant’s two prior felony drug convictions
qualified him as a career offender under 21 U.S.C.
§§ 841(b)(1)(A) and 851(a)(1), as well as § 4B1.1 of the Sen-
tencing Guidelines, thereby triggering a mandatory minimum
sentence of life imprisonment. Although Defendant stipulated
726                 UNITED STATES v. MAUSALI
to his prior felony convictions, and conceded that he qualified
for the statutory mandatory minimum of life imprisonment, he
argued that neither the Guidelines nor the statutory career
offender enhancements should apply because his prior crimes
involved relatively small drug amounts. The district court ulti-
mately rejected these arguments and sentenced Defendant to
life in prison for the drug conspiracy charge. Defendant also
received concurrent terms of 240 months’ imprisonment on
the robbery conspiracy charge and 120 months’ imprisonment
on the § 922(g) charge, plus a consecutive term of 120
months’ imprisonment on the § 924(c) charge. Defendant
timely appealed.

II.    Discussion

  We have jurisdiction pursuant to 28 U.S.C. § 1291 and 18
U.S.C. § 3742(a). For the following reasons, we affirm both
Defendant’s conviction and his sentence.

  A.    Outrageous Government Conduct

   Defendant contends that the district court abused its discre-
tion by failing to sua sponte dismiss the indictment in the face
of the Government’s purportedly outrageous conduct. Defen-
dant claims that the Government violated his right to due pro-
cess by supposedly directing the entire criminal enterprise
from start to finish and by promoting a crime of violence. We
do not reach the merits of Defendant’s outrageous govern-
ment conduct claim, because Defendant has waived this claim
for purposes of appeal.

   [1] The Second, Third, and Eighth Circuits require a defen-
dant to assert outrageous government conduct of which he is
aware before trial, pursuant to Fed. R. Crim. P. 12(b). See,
e.g., United States v. Nunez-Rios, 

, 1098-99 (2d
Cir. 1980); United States v. Pitt, 

, 760-61 (3d
Cir. 1999); United States v. Henderson-Durand, 

, 973-74 (8th Cir. 1993). The policy behind the rule is
                      UNITED STATES v. MAUSALI                         727
sound. Outrageous government conduct claims involve
alleged “ ‘defects in the institution of the prosecution’ itself,”
questions of law that the court should decide before trial.

(quoting what is now Fed. R.
Crim. P. 12(b)(3)(A)); accord 

. Further-
more, pretrial assertion of the claim permits the trial court to
“conduct a hearing with respect to any disputed issues of
fact.” 

. Indeed, the Federal
Rules of Criminal Procedure require a defendant to “alleg[e]
a defect in instituting the prosecution” before trial, Fed. R.
Crim. P. 12(b)(3)(A), or else waive the objection on appeal,
Fed. R. Crim P. 12(e); we apply a similar waiver rule to
untimely claims of irregularities in grand jury proceedings.
See United States v. Kahlon, 

, 469 (9th Cir. 1994)
(“[I]rregularities in grand jury proceedings are considered to
be defects in the institution of the prosecution within the
meaning of Rule 12(b)[ ] . . . . Failure to raise such defects
before trial results in waiver of the objections.” (internal quo-
tations and citations omitted)).

   [2] In this case, Defendant waived his outrageous govern-
ment conduct argument by failing to raise it before trial.
Although we may grant relief from a waiver if the defendant
“present[s] a legitimate explanation for his failure to raise the
issue in a timely manner,” United States v. Anderson, 

, 669-70 (9th Cir. 2006), Defendant has offered no
explanation whatsoever, and we find none in the record.
Defendant knew of the factual basis supporting his claim at
least six months before trial began, when the indictment issued.1
  1
    Defendant alleges that the Government “initiated the criminal activity
and engineered the criminal enterprise from start to finish”; “suggested the
idea of a home invasion robbery” and sought “to recruit individuals to
itself to create a robbery ‘crew’ ”; “supplied a motel room, a rental car, a
bullet proof vest and duct tape”; withheld the location of the purported
stash house from the crew; “suggested the robbery be for cocaine”; dic-
tated the date of the robbery; provided the crew with a floor plan of the
stash house; and “urged [him] and the others to perform the crime armed
with guns.” Not only do all of these material facts appear in the indictment
itself, but Defendant had personal knowledge of these material facts.
728                UNITED STATES v. MAUSALI
Despite this, he raises outrageous government conduct for the
first time on appeal and argues that the district court should
have dismissed the case on this basis sua sponte. We hold that
this issue is waived.

  B.   Defendant’s Remaining Arguments

   [3] The remainder of Defendant’s myriad claims are either
waived or meritless. Defendant waived his argument that the
district court erroneously failed to sever his and Mose’s trials,
because he neither moved for severance before trial nor joined
Mose’s pre-trial severance motion. See Fed. R. Crim. P.
12(b)(3)(D), (e); United States v. Yarbrough, 

,
1531 (9th Cir. 1988). We decline to excuse these failures on
Defendant’s theory that it would have been an “unnecessary
formality” for him to move for severance in light of the dis-
trict court’s denial of Mose’s motion. Although we may
excuse a defendant’s failure to renew his severance motion at
the conclusion of the government’s case-in-chief as an unnec-
essary formality, see United States v. Sullivan, 

,
981 (9th Cir. 2008), we have never excused an outright failure
to raise the issue on that basis, and we will not do so here.

   [4] Moreover, the district court did not commit plain error
by failing to question each member of the jury for taint after
dismissing and replacing the juror who could no longer con-
tinue deliberating. Upon learning of one juror’s potential bias,
the district court promptly and appropriately convened a hear-
ing on the matter. See United States v. Angulo, 

,
847 (9th Cir. 1993). The meticulous and highly experienced
district judge thoroughly questioned the juror—who testified
that he had not shared the basis of his problem with the other
jurors—and properly replaced the juror with an alternate.
None of the parties objected to this action or requested any-
thing further, even when given the opportunity to do so. The
district court’s factual determination that the partial juror had
not tainted the rest of the panel was not clearly erroneous, see
                    UNITED STATES v. MAUSALI                 729
United States v. Elias, 

, 1020-21 (9th Cir.
2001), nor was there any plain error.

   [5] In addition, existing circuit precedent forecloses Defen-
dant’s constitutional challenges to the statutory mandatory
minimum life sentence he received for being a career drug
offender, pursuant to 21 U.S.C. §§ 841(b)(1)(A) and
851(a)(1). See United States v. Jensen, 

, 707 (9th
Cir. 2005) (rejecting argument that 21 U.S.C. § 851(a)(1)
impermissibly vests sentencing discretion in the executive
rather than the judicial branch and “infringes on the ability of
the district court to impose a sentence of less than life impris-
onment”); 

(rejecting argument that “the sentencing
scheme imposed a sentence that was not ‘proportional’ to the
crime . . . in violation of the Eighth Amendment,” in light of
the Supreme Court’s decision in Harmelin v. Michigan, 

, 1001 (1991)); see also United States v. Van Win-
row, 

, 1071 (9th Cir. 1991).

   Finally, because Defendant rightly concedes that his prior
felony drug convictions alone triggered § 841(b)(1)(A)’s stat-
utory mandatory minimum life sentence, and because the dis-
trict court sentenced him to life under the statute, we need not
resolve Defendant’s argument that his prior convictions were
insufficient to trigger the Guidelines’ career offender
enhancement, U.S.S.G. § 4B1.1.

III.   Conclusion

  For the foregoing reasons, the judgment and sentence are
AFFIRMED.