A recorder is frequently a good idea when you think that you might get into a confrontation with an authority figure. Sometimes it is a benefitto create an accurate record of what takes place.
But check your local state laws if you are contemplating surreptitiously recordinga conversation. In some states, like Maryland, it is illegal to record unless all parties to the conversation consent, and an illegal recording cannot be used in court. In certain states andcircumstances, it can also get you in trouble.