A person is guilty of custodial interference in the first degree when he commits the crime of custodial interference in the second degree:
It shall be an affirmative defense to a prosecution under subdivision one of this section that the victim had been abandoned or that the taking was necessary in an emergency to protect the victim because he has been subjected to or threatened with mistreatment or abuse.
Custodial interference in the first degree is a class E felony.
N.Y. Penal Law § 135.50