The police wont get involved here either if it is a matter of contempt. HOWEVER, if you write into the parenting plan that IF you suspect he is under the influence, you WILL call the police and have him given a breathalyzer, then they will have to be involved.
Im a little worried about your counselor suggesting your implement a plan as co parents as part of a plan to leave...
If I could have had a co parenting plan with my xAH that we came up with and agreed upon, that would have meant he could communicate, was willing to work together and cared equally about the kids.... Those were all the issues we fought about bc an A cares about an A and not all that "unnecessary communicating crap" (my xahs line).
So it seems naïve on a counselors part to suggest that you delay leaving or asking him to leave until you establish a plan together.
I stayed and tried that for almost a year- I wanted to avoid using lawyers and having it be nasty and thought we could negotiate it together.... That did NOT work at all.
ONLY after I had a lawyer and we were in court and he saw I was serious about protecting the kids did he have any interest in developing a plan together and that I believe is ONLY bc he is now interested in his image to the court.