Why can't a law be ped in all of the states requiring a paternity test at birth to avoid paternity fraud?

Currently in most states if you're married then you're automatically considered the father of a child born to your spouse. If you're unaware of possible infidelity, you're not thinking of getting a paternity test. You're likely not to bring the issue up because you're being misled. If you find out later, that you're not the biological father, you're still liable for child support because you didn't question paternity within a specified time limit. The worst part is that Census numbers indicate that women lie in these cases 30% of the time. So, strikingly, there are a lot of men supporting children who aren't their own. The other troubling part is that you can't make this behavior a crime. It should be a felony to do this. If a man doesn't pay child support,in most statutes he's convicted of felony. However, if a woman commits paternity fraud, there is no legal recourse civilly nor criminally for the man. This is a serious inequality of the law; no equal protection.