Robert Haddix, Jr., Texas prisoner # 1175826, filed a 42 U.S.C. § 1983 complaint alleging that the defendants had conspired to deny him a fair and impartial trial. The district court held that Haddix’s claims were barred by Heck v. Humphrey, 512 U.S. 477, 114 S.Ct. 2364, 129 L.Ed.2d 383 (1994). Haddix has failed to brief the district court’s Heck determination, and, therefore, that issue is waived and unreviewable. See Yohey v. Collins, 985 F.2d 222, 224-25 (5th Cir. 1993). He consequently cannot show the district court’s resolution of his claims to be erroneous.

Haddix’s appeal therefore lacks arguable merit and is dismissed as frivolous. See 5th Cir. R. 42.2; Howard v. King, 707 F.2d 215, 219-20 (5th Cir. 1983). Haddix is warned that the dismissal of this appeal as frivolous counts as a strike for purposes of 28 U.S.C. § 1915(g). See Adepegba v. Hammons, 103 F.3d 383, 387 (5th Cir. 1996). We warn Haddix that once he accumulates three strikes, he may not proceed in forma pauperis in any civil action or appeal filed while he is incarcerated or detained in any facility unless he is under imminent danger of serious physical injury. See 28 U.S.C. § 1915(g).

APPEAL DISMISSED; STRIKE WARNING ISSUED.