Sergeant Daniel Hood told Malachy that he could have him arrested for drinking in public. Which is technically true but Malachy's charge would be Public Intoxication. Not for drinking in public but for being intoxicated in public.
When Rhodes and Costello interrogate Malachy, Rodney says "Come on Skipper! This is enough of this. Just tell Rhodes what he wants to know?"
Though it isn't quite clear what it is that Rhodes wants Malachy to tell him, Rhodes likely wants Malachy to tell him where Jake and Leslie are hiding.