Wyo. Stat. § 6-2-105: Manslaughter; penalty.

(a) A person is guilty of manslaughter if he unlawfully kills any human being without malice, expressed or implied, either:

(i) Voluntarily, upon a sudden heat of passion; or

(ii) Involuntarily, but recklessly except under circumstances constituting a violation of W.S. 6-2-106(b).

(b) Except as provided in W.S. 6-2-109, manslaughter is a felony punishable by imprisonment in the penitentiary for not more than twenty (20) years.