Gene Leonard Smith pleaded guilty to conspiracy to distribute and possess with intent to distribute five-hundred grams or more of a methamphetamine mixture, in violation of 21 U.S.C. §§ 841(a)(1), 841(b)(1)(A), and 846; the knowing or intentional use of a person under eighteen years of age in a drug conspiracy, in violation of 21 U.S.C. § 861(a)(1); and knowingly possessing a firearm in the furtherance of a drug-trafficking crime, in violation of 18 U.S.C. § 924(c)(1)(A). The district court 1 sentenced Smith to the mandatory statutory minimum of life imprisonment for the drug offenses given Smith’s two prior drug felonies, see 21 U.S.C. §§ 841(b)(1)(A) and 851, and a six *524 ty-month consecutive sentence for the use of a firearm in furtherance of the drug crimes. See 18 U.S.C. § 924(a)(1). Smith appeals, claiming that the district court erred in refusing to compel the government to file a motion for downward departure pursuant to 18 U.S.C. § 3553(e). We affirm.
I.
As part of his plea agreement, Smith agreed to cooperate with law enforcement in the investigation and prosecution of his co-conspirators. The agreement explicitly provided that if the government, in its “sole discretion,” concluded that Smith provided “substantial assistance” in the investigation and prosecution of other persons connected to the drug conspiracy, then it “may,” but would “not be required to,” move for a downward departure under § 3553(e) and/or U.S. Sentencing Guidelines § 5K1.1. See 18 U.S.C. § 3553(e) (“Upon motion of the Government,” the district court may depart from the statutory minimum sentence “to reflect a defendant’s substantial assistance in the investigation or prosecution of another person.”); USSG § 5K1.1 (authorizing a departure from the Guidelines sentence “[u]pon motion of the government stating that the defendant has provided substantial assistance in the investigation or prosecution of another person”).
In accordance with his plea, law-enforcement officers debriefed Smith for two days. He took and passed a polygraph test when officers raised questions about his truthfulness. On July 3, 2008, Smith testified for the government at co-defendant Leodan Vasquez’s sentencing hearing. Smith also testified as a prosecution witness during the trial of co-defendant Jose Juan Islas-Bravo on July 23, 2008. At that proceeding, Smith appears to have testified in accordance with the proffer he made in his debriefing sessions. The government did not introduce additional evidence to corroborate Smith’s testimony. When addressing Vasquez’s motion to acquit, however, the district court expressed doubts about Smith’s credibility as a witness in that case, stating that it had “strong feelings” about Smith’s “lack of credibility.” The district court also appeared concerned over whether Islas-Bravo’s conviction could be based on Smith’s statements alone. Smith claims that instead of remaining “mute” in the face of the district court’s statements, the government should have mentioned evidence corroborating his story so as to assure the district court that Smith was a reliable witness. Ultimately, the jury acquitted Islas-Bravo of the criminal count for which Smith’s testimony had provided the only evidence.
Despite Smith’s debriefing and testimony, the government declined to move for a lesser sentence under either § 3553(e) or § 5K1.1. Smith filed a motion to compel the government to file a substantial-assistance motion under § 3553(e), claiming that its failure to do so had violated Smith’s plea agréement. At sentencing, the district court found that “because the plea agreement broadly reserves the decision to make a substantial assistance motion [to] the sole discretion of the U.S. Attorney’s Office,” there was no breach of the plea agreement. On appeal, Smith contends that the district court erred in denying his motion to compel, alleging that the government’s refusal to file a motion “was based upon an unconstitutional motive, was irrational, and was made in bad faith and for the improper purpose of dictating the length of Mr. Smith’s sentence.” We review the district court’s denial of a motion to compel for abuse of discretion.
United States v. Perez,
*525 II.
Unless a plea agreement provides to the contrary,
see United States v. Holbdy,
As articulated at Smith’s sentencing hearing, the government’s decision not to move for downward departure was based on a variety of factors relating to “the significance of the defendant’s assistance.” The government expressed concerns about the reliability of Smith’s information and his credibility generally, as did the district court in Islas-Bravo’s trial. Additionally, the government believed that given his lack of credibility, Smith was an ineffective prosecution witness. This was supported by the fact that the jury acquitted Islas-Bravo on the conspiracy charge about which Smith testified. Given this “outcome[ ]” and his performance on cross-examination, the government concluded that Smith was “pretty much useless in the future.” In addition to his ineffectiveness as a witness, the government pointed out that Smith’s role in the Vasquez sentencing was minimal: he testified about the price of drugs and Vasquez’s role in the conspiracy. This information provided evidence for the application of a sentencing enhancement.
As further support for its refusal to make the motion, the government noted the timing of Smith’s cooperation. Smith began cooperating with law enforcement after the investigation into the conspiracy had already ended. By the time the government debriefed him and attempted to verify his credibility via polygraph, Smith was only available to testify in the Vasquez sentencing hearing and the Islas-Bravo trial. The government also highlighted as a reason to refrain from moving that Smith had not engaged in “any active” cooperation or investigation on the government’s behalf because he was incarcerated.
In response to the government’s justifications for not filing a motion, Smith has presented no evidence that the decision was based on an unconstitutional motive, such as his race or his religion.
See, e.g., United States v. Moeller,
*526
Smith has also not presented evidence that the government’s refusal to file a substantial-assistance motion was not rationally related to a legitimate end.
See Wade,
Smith also claims that “the government ... based its decision ... on a factor other than the substantial assistance ... because [it relied on the fact that] the trial court had discredited [Smith’s] testimony” in deciding not to move. Contrary to Smith’s claim, however, questions about the credibility of a defendant in a case where the government assistance involves an activity such as providing testimony— whether expressed by the government or a presiding judge — “do relate to the quality of ... assistance.”
See Perez,
Smith’s final claim of improper motive is that the government refused to file the motion “in bad faith” because it was being a “sore loser[]” following its inability to obtain a conspiracy conviction in the IslasBravo trial. We conclude that Smith has only set forth “ ‘generalized allegations of improper motive,’ ” which are insufficient to make the threshold showing required for relief.
See Perez,
In conclusion, because we hold that Smith has failed to meet the threshold showing of improper motive, the district court did not abuse its discretion in refusing to compel the government to file a § 3553(e) motion.
See id.
at 1139;
see also Moeller,
III.
Finally, Smith argues that the doctrine of judicial estoppel should have prevented the government from arguing at his November 6, 2008 sentencing that *527 Smith did not provide substantial assistance. Smith claims that the government’s position during his sentencing was “clearly inconsistent” with its position in the October 16, 2008 appellate brief it submitted to this court in co-conspirator Vasquez’s sentencing appeal. In that brief, the government argued “that the district court had committed no error by relying upon [Smith’s testimony] in imposing a three-level sentencing enhancement” at Vasquez’s sentencing hearing. We disagree with Smith.
Judicial estoppel is an equitable remedy fashioned “to protect the integrity of the judicial process by prohibiting parties from deliberately changing positions according to the exigencies of the moment.”
New Hampshire v. Maine,
IV.
For the foregoing reasons, we affirm the judgment of the district court.
Notes
. The Honorable Mark W. Bennett, United States District Judge for the Northern District of Iowa.
