Wyo. Stat. § 9-3-422

(a) Except as specified for law enforcement officers under W.S. 9-3-432, any member in service who has ten (10) or more years of service credit during which contributions have been paid because of illness or injury outside of or in the scope of employment, or any firefighter member in service for whom contributions have been paid because of injury in the scope of employment, may retire on account of a total or partial disability in accordance with rules and regulations adopted by the board. In determining mental or physical incapacitation for disability retirement under this section, the board may require physician reports, medical examinations, functional capacity evaluations, vocational examinations and other necessary reports and examinations for purposes of this section. The costs of any functional capacity evaluation, vocational examination or other specialized test required under this subsection shall be paid from the retirement account.

(b) Upon retirement for a total disability and except as provided under W.S. 9-3-431(f) and 9-3-432(h), a member shall receive a monthly disability retirement benefit for the period of his disability equal to one hundred percent (100%) of his service retirement benefit under this article as if the member was eligible for normal retirement benefits. Upon retirement for a partial disability, a member shall receive a monthly disability retirement benefit for the period of his disability equal to fifty percent (50%) of the normal retirement benefit payable to the member as if the member were eligible for normal retirement benefits. Disability benefits are payable for the life of the member or until the member is no longer disabled.

(c) Any employee granted disability retirement under this section shall at the time retirement is granted, elect to receive either the benefit authorized by this section or one (1) of the joint and survivor benefit options specified in W.S. 9-3-420.