Mr. Schiavo & Adultery

From a reader re:  "Is Terry Schiavo Less Than a Junkyard Dog?":

Just one little note on the Schiavo case, which I have not followed closely until recently. The article mentions that the husband is  "openly adulterous." Just consider for a moment how different the case might look if adultery were illegal as until a generation ago it was nearly everywhere. It would be much harder to defend him as a viable guardian if he were a criminal!

Isn't this exactly the sort of case that prompted repeal of adultery laws? How cruel and heartless of society (it was said) to make it a crime for a man whose wife is permanently incapacitated to seek a little satisfaction elsewhere. Yet the effect is that a man in a sexual relationship with another woman can still claim the rights of a husband with respect to his legal wife.

I have long found it curious that so few conservatives publicly call for the reinstatement of adultery laws, because to me there is a clear  "seamless garment" argument to be made connecting the legalization of adultery with the decline of marriage (indeed it's more obvious than the problem with  "gay" marriage). Personally I would favor making adultery a low-grade misdemeanor. This case well illustrates the unintended consequences that can flow from supposedly compassionate law.