Are the police required to enforce a court ordered parenting time?

Long story short, my son has a four month old daughter. The mother is a nutcase (but that’s neither here nor there.)

My son went to court three weeks ago to get parenting times set in “stone” by a judge (at this point it’s ordered 50/50, but that may very well soon change in my son’s favor due to the fact that the mother is a nutcase, but that is neither here nor there.)

Last night he went to pick the baby up at 8:00, but, long story short, the mother refused to turn the baby over (because she is a nut case but that is neither here nor there.)

He took the legal documents detailing the parenting time to the police, showed them to them and they told him he was SOL.

Can they do that? Would they have done something different if it had been my son who refused to turn the baby over to the mother?