Originally Posted by Red__Zed

They'll usually ticket you based on judgment, but I know it parts of nova they carry a candela meter. The document I linked earlier describes what is allowed and how it is measured...and light emissions are usually measured at the source.

They have the option to eyeball it and give you the ticket, but if you are irritating them, they can keep you on the side of the road "measuring" from every angle for hours.