I’m not a lawyer but the legislation says: Lights must be on when wipers are in constant use

IMO this would mean: using your wipers a few times just to clean washer fluid off the windshield? Not turning the lights on.

Using them once a minute in a light drizzle? Turn them on.

Perhaps there is some leeway in defining “constant” but the law also mentions decreased visibility in addition to constant wiper use.

> §2067. Lights

>1. Display of headlights. A vehicle located on a way must be equipped with headlights as described in section 1904. The headlights must be illuminated:

>A. During the period from sunset to sunrise; [PL 2015, c. 51, §1 (AMD).]

>B. At any time when, due to insufficient light or unfavorable atmospheric conditions, including, but not limited to, rain, freezing rain, fog or snow, persons or vehicles on the way are not discernible for a distance of 1,000 feet ahead; and [PL 1997, c. 249, §1 (NEW).]

>C. At any time when windshield wipers are in constant use. [PL 1997, c. 249, §1 (NEW).]