konceptjones
The one between three and three.
In cases of domestic violence.
It's easier for some women to have the child without involving the father. If the tests were mandatory, then a woman in this case would be stuck co-parenting with an abuser.
Women are statistically more likely to be abused while pregnant, so this would screw a lot of women who just want to escape without being tied to their abusers.
The problem here is that in many states (maybe most of them?), if she ever needs assistance the courts will demand a DNA test so they can put dude on child support, so there's a chance she may wind up co-parenting with him anyways.