Chuck,
I had a FO accused of having alcohol on her breath by a screener back before the TSA days. The first thing I did was call ALPA. Our union reps took the ball from there. The flight was canceled and the accusation was proven to be false. Seems the screener didn’t think a woman should be flying an airplane.
The point being the job of the union is to defend and protect pilots to the best they can...it is the reason we pay dues. You seem to assume the pilot in this case is guilty even though he has yet to actually be charged of anything.
When I first upgraded to 767 Captain 7 years ago, there was a similar pilot booze incident in the news. I was in PHX and just walking to the cockpit when a pax in first class asked me "Are you drunk too?" I immediately told him "No, but you just cancelled the flight". I then went to the PA and said "Ladies and gentlemen, this is the Captain. Unfortunately one of you fellow passengers just asked me if I was drunk. While I am not drunk and have not had any alcohol for over a week, to protect my pilot's license, my FAA medical, my livelihood, my family welfare and my company I must now get alcohol tested by a medical facility before I can fly the plane. Since this is not a Hawaiian pilot base there are no reserve pilots in Phoenix to take my place as your Captain and fly the plane. Therefore I regret to tell you this flight is cancelled. If you remain in your seats for a few minutes, I'll get the station manager so she can explain to you what is going to happen next. Thank you and I deeply regret the inconvenience."
I then called first my union rep and then the CP to tell them what happened. The CP had me go to the drug/alcohol testing center the station personnel used and get both a breath and urine test. I offered to do blood too but he said that wasn't necessary. I deadheaded home the next day when I replacement Captain came to PHX. I had about 5 days off with pay protection for missed flights while I waited for my 0% alcohol test to come back. Was this all necessary? I knew I was 0% alcohol but if I didn't get tested and flew, I could never 100% protect myself.
When the pax were in the gate area fuming about not getting to Honolulu when they were supposed too, I thought they were going to kill the pax who asked me if I was drunk. He started yelling at me across the lobby saying he was kidding and calling me all sorts of bad things. The station manager had him escorted off by police and banned him from ever flying on Hawaiian again. Since he was a Hawaii local, this hurts as there aren't a lot of interisland options when he's home and wants to go to another island. Fuck him. He's luck Hawaiian didn't sue him for the cost of the cancelled flight / rebooking all the pax.