It's The Law: Specifically for Skiing

Vessel operators towing a person(s) on water skis or a similar device have additional laws they must follow.

Requirements for Towing Skiers

It is illegal for boats or PWCs to tow persons on water skis, a skiboard, or any device of this type between sunset and sunrise.
It is illegal for the operator of the towing vessel or person(s) being towed to be under the influence of alcohol or drugs.
A boat or PWC must not tow persons on water skis or similar devices within 100 feet of a vessel not underway or adrift, a dock or pier, a bridge, a person in the water, a shoreline adjacent to a residence, a public park or beach, a swimming area, a marina, a restaurant, or any other public use area.
The person being towed must wear a ski belt; ski jacket; or Type I, II, or III personal flotation device that is properly fitted and fastened.
Every boat towing a person(s) on water skis or a similar device must have on board:
- A person, in addition to the boat operator, capable of observing the towed person(s) at all times or ...
- A wide-angle rearview mirror mounted such that the operator can observe the towed person(s) at all times.
Every PWC towing a person(s) on water skis or similar device must be rated by the manufacturer to carry three or more persons and must have on board a person, in addition to the PWC operator, capable of observing the towed person(s) at all times. A wide-angle mirror may not be used in place of an observer on PWCs.