young men are told. >> reporter: michigan state senator rick jones helped write the state's sex offender registry law. he said zach should have been more careful. >> i would hope somebody 19 years old would say, well, do you have a driver's license? you don't appear to be the appropriate age. >> it's crazy. it's like a split decision, like a small decision, know what i mean? and your life can affect everything that you do. >> reporter: making matters worse for zach, michigan does not provide an automatic defense for when a girl lies about her age. >> if he gained in this behavior 20 minutes across the state line, he wouldn't have been charged at all. >> the law unfortunately at this time in michigan doesn't have the same protection as indiana and 19 other states. >> this will be plenty of people who say, those laws are on the books for a reason, to protect minors from sexual predators. >> we're not talking about loosening the law. no one's indicating that somebody who preys on a...