I agree with Laurie....stress the safety of your children and others on the road, and you won't come across as "just an angry wife". I would write down all the instances you can think of that you know he's driven under the influence since you made the decision to not let him drive high. When you start listing off these times, in specifics, you probably won't have to get too far down the list before the judge sees the light.
It doesn't have to be detailed..just like you said here "the time you came to get the trailer and you were high and I told you you didn't need to be driving"...if your family has been witness to it, just mention it. Judges are used to families taking sides, but even though it's just your word against his, being specific will help.
I agree..he's not a good driver...he's just lucky he hasn't gotten caught and everyone else is lucky he hasn't hurt/killed someone.
Hugs and prayers!
Amy