I wouldn't be too concerned if they had been charged with something in the past. It could be something that they were truly not guilty of. I remember being accused of a crime many years ago that I had absolutely nothing to do with. Fortunately, the authorities saw it this way too before any charges were made.
If past transgressions resulted in criminal charges and conviction, I would be most concerned. Those that either attempt to hide, cover up or claim ignorance when they are found out would be off my list, regardless of how I intended to vote beforehand.
Nobody forgets being charged with something. Ford chose to try to hide the marijuana thing. That, in my opinion, is worse that being charged with the marijuana possession.