In some states, it is illegal for you to record a conversation without the other party's consent. If you are hauled into court, your recording may be (1) used to chain another charge on you, or (2) be inadmissible as exonerating evidence. Some courts have ruled that LEOs can be recorded while performing official duties, but I don't think there is a definitive SCOTUS decision on this subject, and I wouldn't bet my freedom on this.