There is a reason why there used to be chastity belts, and it wasn't to protect against rape. In all likelihood, the 16 year old was looking and found. That said, there seems to be nothing here to tell the actual character of the 22 year old or the 16 year old. I lived in the Mid-South. The father's actions could get him sued successfully, but worse, it could get the young man attacked or injured or killed if some Yahoo takes it upon himself to "protect children."
Take a long, hard look at the scenario in law. A high school senior at 16 or 17 chooses to sleep with his college age boyfriend, a hugely common scenario. His irate father could do the same sign and ad "Gay man molested my child" to the sign, and I guarantee you the man would be attacked and run out of town or killed. Encouraging the libel is encouraging a morality that is subjective, not legal, and more importantly, a wrong definition of child molestation, which damages the term when it actually does apply. Statutory rape and child molestation should be different categories as they involve hugely different psychological and legal matters.
I taught high school sophomores for five years, so I've worked directly as an adult with thousands of them. A lot needs to be included here instead of the broad brushes.
The state acknowledges the age of consent as 16, not adulthood. Those are not equal. She is a minor, but not merely a child. The state has good reason to make such a distinction, as the free agency of 16-year-olds is not merely some relic of a rural past, but of a mixed status that also exists in other key areas of status. Drivers licenses and alcohol and military enrollment have all been set at less than 21 in many areas of the country, only becoming more uniform once the insurance companies pushed.
Just because something is legal doesn't make it right. She might be 16 but she is her father's baby. He's protective and wants the best for him. A 22 year old married man is not the best for her. I wonder how many other teenagers he has seduced. His wife is probably 14.
What if the 22 year old was forced into a teen pregnancy marriage? He could have been married four years or more already to some gal he had nothing more in common with than both of their teenage hormones. That he might be seeking a partner still is possible. Or, he could merely be a scumbag.
The frequent interplay of young legal adults and teenage minors is not rare, not unusual, and not unnatural. It is perfectly normal for a 22 year old and a 16 year old, if both are sexually active and looking, to find one another. The suggestion that age 21 is some magical barrier is hugely injected into biology AND society.
As for the father, it is too hard without being personally acquainted to determine if this is some misguided attempt at "protecting" his promiscuous teen, or at spiting her now because he hasn't been able to punish her boyfriend or control her.
It also remains to be shown how far apart the mental ages of these two lovers were. Generalizations about 16 and 21 are just that. Individuals vary, and he might be very close to her age mentally or vice versa.
I'd rather save my outrage for actual crime and cases where the victim wasn't sneaking out to have a rendezvous, and possibly already long past virtue when she met him. Again, we don't know. It could be just as manipulative from the 22 year old as some allege, or not. In order to cast the man in the role of predator, the behavior needs to be proven, not assumed. Many 16 year olds actively seek young 20's both online and in person, so it by no means requires some anonymous predator trawling the web to find a naive waif nearby.
I suggest not trying to stir the pot on this one. I also can't answer you in a manner you would understand because I suspect you know jack shit about how laws are created or modified in the USA, let alone state vs federal regulations.
I'd argue with you. He doesn't know Jack. He does know shit. Read his on-topic threads on both subjects.
