N.Y. Police Certain Municipalities 360/11 § 2: No title

§ 2. The tours of duty of sergeants, roundsmen, patrolmen, (not

including detective sergeants) on duty in the open air, on the streets

or other public places of a city of the first class or a city of the

second class shall be changed at least once in each calendar month.

Provided, however, that in cities of the first and second class which on

December thirty-first, nineteen hundred and ten, had in force and

operation a three platoon system, the tour of duty of such platoons and

each member thereof, and the manner of changing such tours of duty may,

at the election of the local authorities, having the management, control

or direction of the police force, be and continue as the same were in

force and in operation on said December thirty-first, nineteen hundred

and ten.