Okla. Admin. Code § 590:10-10-6
An otherwise eligible Surviving Spouse of an employee killed or mortally wounded in the performance of his or her duties with the Department of Corrections shall not receive benefits as provided in Title 74 O.S. Section 916.3 if he or she is receiving or elects to receive any type of survivor benefits from the Oklahoma Firefighters Pension and Retirement System, the Oklahoma Police Pension and Retirement System or the Oklahoma Law Enforcement Retirement System on account of this or any spouse. The Surviving Spouse must make an irrevocable election of benefits within ninety (90) days of eligibility for benefits. The Surviving Spouse cannot receive surviving spouse benefits for more than one member of the specified retirement systems. Receipt of benefits from any such retirement system shall be presumed to constitute such an election. The Surviving Spouse must certify annually that he or she is not receiving any type of survivor benefits from another state retirement system.
Okla. Admin. Code § 590:10-10-6