It’s a question that comes up often after a new law is challenged under the single-subject rule of the Pennsylvania Constitution: Why combine seemingly unrelated imperatives into one piece of legislation?

And one justice of the Pennsylvania Supreme Court posed it point blank to an attorney for the Pennsylvania General Assembly last week during oral arguments in Philadelphia, in a case over whether several changes to Megan’s Law — including one criminalizing failing to register as a sex offender — were part of an act that violated the single-subject rule of the state constitution.