SUMMARY ORDER

BACKGROUND

In these tandem appeals, defendant-appellant Shane C. Buczek, proceeding pro se, appeals from two judgments of the District Court convicting him, following guilty pleas, of (1) one count of possession of a false identification document in violation of 18 U.S.C. § 1028(a)(4), and (2) one count of contempt of court in violation of 18 U.S.C. § 401(3). We assume the parties’ familiarity with the underlying facts, the procedural history of the case, and the issues presented on appeal.

DISCUSSION

A.

First, Buczek argues that he did not knowingly waive his right to counsel because the District Court failed to provide him, during his March 2010 plea allocution on the above charges, with the colloquy required by Faretta v. California, 422 U.S. 806, 95 S.Ct. 2525, 45 L.Ed.2d 562 (1975). But in Buczek’s related criminal appeal, in which he challenged his bank fraud conviction, we held that his waiver of the right to counsel was knowing and intelligent. See United States v. Buczek, 457 Fed.Appx. 22, 25 (2d Cir. 2012) (non-precedential summary order). The reasoning of that decision is equally applicable to Buczek’s present appeals inasmuch as the pretrial proceedings in these three criminal cases were intertwined and Buc-zek’s plea allocution on the false identification and contempt of court charges took place only three weeks after the conclu *106 sion of his jury trial on the bank fraud charge.

Second, Buczek has waived his argument that his indictment on the false identification charge should be dismissed due to a purported violation of the Speedy Trial Act because he did not raise that argument in his opening brief. See JP Morgan Chase Bank v. Altos Hornos de Mexico, S.A. de C.V., 412 F.3d 418, 428 (2d Cir. 2005); LoSacco v. City of Middletown, 71 F.3d 88, 92-93 (2d Cir. 1995) (explaining that a pro se appellant abandons an issue not raised in his appellate brief). Moreover, even if we were to consider the Speedy Trial Act claim, we would conclude that it was waived by Buczek’s valid guilty plea. See United States v. Coffin, 76 F.3d 494, 496 (2d Cir. 1996) (holding that “[a] knowing and voluntary guilty plea waives all nonjurisdictional defects in the prior proceedings”).

Finally, Buczek’s argument that the contempt of court statute, 18 U.S.C. § 401(3), is not an “indictable offense” is without merit. See United States v. Guariglia, 962 F.2d 160, 162 (2d Cir. 1992); United States v. Morales, 566 F.2d 402, 404 (2d Cir. 1977) (“Many cases have tacitly or explicitly recognized the power of grand juries to hand down indictments charging criminal contempt.”).

For these reasons, we reject all of Buc-zek’s claims in these tandem appeals. Accordingly, all of his motions that are currently pending are denied as moot.

B.

As a final matter, we note that, during the pendency of these appeals, multiple panels of this Court have dismissed as frivolous approximately thirteen of Buc-zek’s related appeals taken from meritless post-judgment motions he filed in the District Court. In addition, Buczek has filed innumerable frivolous motions in his present appeals, which have greatly delayed the resolution of these matters. Even taking into account Buczek’s pro se status, such litigation practices are entirely unacceptable.

CONCLUSION

We have considered all of Buczek’s remaining arguments on appeal and find them to be without merit. Accordingly, we AFFIRM the judgments of the District Court and DENY as moot all of Buczek’s pending motions in the captioned cases (U.S.C.A. Dkt. Nos. 10-4753-cr and 10-4768-cr).

Moreover, Buczek is hereby WARNED that his further filing in this Court of frivolous motions, appeals, petitions, or other matters relating to his November 2010 convictions, the criminal proceedings leading to those convictions, or his post-conviction litigation, will result in the imposition of sanctions, including leave-to-file sanctions. See In re Martin-Trigona, 9 F.3d 226, 228-29 (2d Cir. 1993) (recognizing that “courts may resort to restrictive measures ... [with respect to] litigants who have abused their litigation opportunities,” including “subjecting a vexatious litigant to a ‘leave of court’ requirement with respect to future filings”); Safir v. U.S. Lines Inc., 792 F.2d 19, 24 (2d Cir. 1986). 1