If wrong spot to post please direct me

Ok my son (16) no license yet

Has a riding mower he has put some lights on it and removes the deck

And he drives it around to his friends and or into trails/fields he has permission from owners to ride on

Now he has been stopped several times yesterday was last

Some officers say it’s ok others say no way

I’m trying to get clarification on this

When he was last stopped he did not have his slow moving sign on it or his deck he was less than city block from home retuning from field

If he should not be driving it then fine but if he can then I think I need info to back him up

Located in Delhi Ontario