(a) A person commits the crime of unlawful imprisonment in the second degree if he restrains another person.
(b) A person does not commit a crime under this section if:
(1) The person restrained is a child less than 18 years old, and
(2) The actor is a relative of the child, and
(3) The actor's sole purpose is to assume lawful control of the child.
The burden of injecting the issue is on the defendant, but this does not shift the burden of proof.
(c) Unlawful imprisonment in the second degree is a Class C misdemeanor.