Do the police or other agencies ever Do Stop / check Agricultural vehicles/ trailers

It seems to be grass cutting time of the year again in our area.

We get Tractors towing massive trailers containing grass at all times of day and night.

I wonder if they comply with all regulations for both lighting, registration plates, speed and driver and licence regulations. Such as age of driver. Compliance with rules about weight of trailer and whether the driver has taken and passed the Trailer test.