Does a condition that a defendant must not possess any materials depicting sexually explicit conduct violate his right to free speech?

We approved a substantially similar condition in Rearden, where we held that the district court did not plainly err in imposing the condition that the defendant "not possess any materials depicting sexually explicit conduct as defined in 18 U.S.C. 2256(2)." 349 F.3d at 619. We reasoned that "[a] defendant's right to free speech may be abridged to `effectively address [his] sexual deviance problem,'" id. (citations omitted) (alteration in original), even where the defendant was convicted only of transmission of child pornography and not of child molestation. Id. at 620. We have also held that the phrase "sexually explicit conduct" is neither vague nor overbroad. See id.; see also United States v. X-Citement Video, Inc., 982 F.2d 1285, 1288-89 (9th Cir.1992) (holding that definition of "sexually explicit conduct" set forth in prior version of 18 U.S.C. 2256(2) survived vagueness and overbreadth challenges), rev'd on other grounds, 513 U.S. 64, 115 S.Ct. 464, 130 L.Ed.2d 372 (1994).