N.Y. Gen. Mun. Law § 208-G
The provisions of any general, special or local law or any rule or regulation to the contrary notwithstanding, including any rule or regulation of any police department or commissioner or head thereof, any member of a police force of a municipal corporation, including, the definition of municipal corporation in this chapter notwithstanding, the city of New York, may accept any additional place or position in another adjacent or nearby municipal corporation, including the city of New York, provided that such additional place or position is limited to volunteer work as a member or volunteer in, of, or for a community board, not-for-profit corporation, volunteer fire department, or other similar community-oriented entity, so long as any such activity shall occur outside his or her regular hours of duty for not exceeding twenty hours a week and provided that such extra work does not interfere or conflict with his or her regular duties as a member of the force or his or her availability for emergency duty nor affect his or her physical condition to the extent that it impairs his or her ability to efficiently perform such duties, and further provided that the type of activity shall first be approved by the appropriate police department or police commissioner.
N.Y. Gen. Mun. Law § 208-G