VP candidate Palin's daughter's pregnancy highlight US sex law silliness

Essay here. Excerpt:

'The daughter is 17 years old. Her boyfriend is 18 years old. She is five months pregnant. From that we can assume that they, at the very latest, had intercourse sometime in May. The girl will turn 18 in October. We do not know, nor is it anyone’s business, how old she was the first time she had sex with her boyfriend.
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What would have happened had the young couple in question engaged in youthful sexuality in Arizona? There the young man would become both a “father-to-be” and a felon at the same time. Any sexual act by an 18-year-old and a 17-year-old is a felony in Arizona, even if the girl’s mother is running for vice president of the United States.'