I have to point out that while polygamy is illegal in many states, the only states that would even consider prosecuting it are Utah, Arizona and maybe Texas, and even there generally they will not unless one of the wives is under 18.
In New York a few years ago the New York Times outed some Muslim polygamists, but no one called for a prosecution. Even though in the larger article it was revealed that many of the second wives as 17-year-olds from Ivory Coast getting married by phone to men in their 30s.
In the 1930s Utah was a hot bed for prosecuting polygamists, the mainstream Mormons wanted to have nothing to do with the continuation of the practice, but after sending waves of men to jail and the practice continuing, they largely gave up on it until the 1990s, when a new wave started of focusing on underaged marriages instead of plurality in prosecution. No one is sure the courts will even uphold laws making polygamy by adults a prosecutable offense, but no prosecutor seems to want to have the case that would decide it on their hands, so Clark really would not have to worry about prosecution.
Now, Mayson being able to be a polygamist and an assistant DA is a bit less likely. But hey, if we accept guys can fly, I guess accepting the US not having anti-polygamy laws is possible.
