Well, I waded through the pile of human misery that was the law review article about legal protections for rapedaddies, and here are the 16 states that provide SOME provisions for stripping rapedaddies of their custodial rights:
California
Connecticut
Idaho
Louisiana
Maine
Michigan
Missouri
Montana
Nevada
New Jersey
North Carolina
Oklahoma
South Dakota
Tennessee
Texas
Wisconsin
If your state isn't on that list, then you live in a state that believes children are best served when they're raised by rapists! Hooray!