Any member of the retirement system who, on or after January 1, 1995, is on leave of absence for the purpose of serving as a state legislator, may elect to continue to be a member of this retirement system. The member shall continue to receive service credit subject to the following:

(1) The member will not receive more than one month's service credit in a calendar month;

(2) Employer contributions shall be paid by the legislature;

(3) Contributions shall be based on the regular compensation which the member would have received had such a member not served in the legislature;

(4) The service and compensation credit under this section shall be granted only for periods during which the legislature is in session; and

(5) No service credit for service as a legislator will be allowed after a member separates from employment with the Washington state patrol.