Maryland Code, State Personnel and Pensions § 26-304

(1) the member's service credit transferred from a retirement or pension system under Title 37 of this article;

(2) for a member who has transferred from the Employees' Retirement System, the member's creditable service recognized under the Employees' Retirement System through the date before the member became a member of the Law Enforcement Officers' Pension System; and

(3) for a member who has transferred from the Employees' Pension System, the member's eligibility service recognized under the Employees' Pension System through the date before the member became a member of the Law Enforcement Officers' Pension System.