A federal law criminalizing sex trafficking passes muster under the U.S. Constitution, a judge held Thursday.In a written opinion, U.S. District Judge Harry D. Leinenweber rejected arguments that 18 U.S.C. Section 1591 is unconstitutionally vague and overbroad.Section 1591 outlaws sex-trafficking ventures that affect interstate or foreign commerce.The law prohibits recruiting, soliciting or patronizing someone while knowing that force, threats or fraud will be used to make the person engage in a commercial sex act.The …