SPRINGFIELD — The Illinois Supreme Court has ruled that a state law restricting where previously convicted child sex offenders can live is constitutional, although it left open the possibility that it was improperly applied to one individual.In a 6-0 decision, the court found the residency restriction “does not infringe upon a child sex offender’s fundamental rights” and that there was a “rational basis” for the state to restrict where a person convicted of such a crime can live.&ldquo …