Maryland Code, State Personnel and Pensions § 31-116.1

(c)(1) If a participating governmental unit elects to provide its employees with the Alternate Contributory Pension Selection under Title 23, Subtitle 2, Part III of this article, an employee of the participating governmental unit who is a member of the Employees' Pension System shall be entitled to the benefits as provided in § 23-222 of this article, effective on the later of July 1, 2006, or the date the employee became a member of the Employees' Pension System, unless the employee transferred to the Employees' Pension System from the Employees' Retirement System or Teachers' Retirement System after April 1, 1998.

(2) If an employee of a participating governmental unit transferred to the Employees' Pension System from the Employees' Retirement System or Teachers' Retirement System after April 1, 1998, the employee is not subject to Title 23, Subtitle 2, Part III of this article and is not entitled to the benefits as provided in § 23-222 of this article.