While other states, including neighboring Oklahoma, continue to push offenders away from some neighborhoods, about 45 Texas towns received letters in November from the group Texas Voices for Reason and Justice demanding they repeal residency restrictions. Dozens of these smaller communities have restricted where sex offenders can live — usually with the purpose of keeping them away from schools and other places children gather — but only later learned they've run afoul of state rules. "Unless the Legislature expressly authorizes it, a general-law municipality may not adopt an ordinance restricting where a registered sex offender may live," according to a 2007 opinion signed by then-AG Greg Abbott, who's now Texas governor. Last year, Montana lawmakers made it a felony for high-risk offenders to live or work in some areas, and Oklahoma added playgrounds and parks maintained by a homeowners association to the list of places prohibiting offenders, according to the National Conference of State Legislatures. [...] federal statistics show the overwhelming number of sex abuse cases involving children are perpetrated by a family member or friend of the family, and not an anonymous stranger, he said.