Mr. Monk and the Election - S3-E15
Character mistake: Captain Stottlemeyer uses gloves to pick up the letter found sticking out of the pipe. He doesn't actually put the glove on, but still uses it to avoid getting any of his prints, skin, etc on the paper. But then he uses his other, non-gloved hand to open up the note and hold it, and Monk also touches the letter. If he cared about not contaminating evidence by using the glove, he wouldn't touch it bare handed and if he didn't care about touching the note bare handed, then he wouldn't have used the gloves.
Answer: The two men are trying to work out a secret deal between them without involving the union, which means the workers' interests aren't being represented and defeats the whole purpose of a union. The mayor would lose labor's support and Cusack's union troubles would just be starting.
Captain Defenestrator