California
Every trailer and semitrailer manufactured after 1940 with a GVW of 6,000 lbs. or more and operated at a speed of 20 mph or more must be equipped with brakes; trailers and semitrailers built after 1966 and with a GVW of 3,000 lbs. or more must have brakes on at least 2 wheels; every trailer or semitrailer built after 1982 and equipped with air brakes must be equipped with brakes on all wheels.
Every trailer coach or camp trailer with a GVW of 1,500 lbs. or more must be equipped with brakes on at least 2 wheels.
Nevada
Every trailer, semitrailer, or pole trailer at least 1,500 lbs. and manufactured after July 1, 1975 must be equipped with service brakes on all wheels.
Trailers, semitrailers, house trailers, or pole trailers, manufactured before July 1, 1975 and weighing less than 3,000 lbs. need not have brakes on all wheels.
Mississippi
Every trailer carrying over 1 ton, when operated on a highway, shall be equipped with brakes adequate to control the movement of the trailer and to stop and hold the trailer.
Brakes on a trailer should be designed so that the driver of the towing vehicle from its cab may apply them.
Brakes on a trailer should be designed and connected so that in case of an accidental breakaway of the towed vehicle, the brakes shall be automatically applied.
Every new trailer, except a trailer of 2 axles of less than 2,000 lbs. GVW towed by an automobile, hereafter sold in this state and operated on the highways, shall be equipped with service brakes on all wheels of every such vehicle.