The phrase "having the law on" refers to a situation where someone is in full compliance with the law. There are several synonyms that one can use to express this condition. For instance, terms like lawful, legitimate, valid, authorized, or permissible can all be used instead of "having the law on." Additionally, words like legal or constitutional can also convey the same meaning. Essentially, these interchangeable terms are used to describe a legal status in which an individual or entity is acting within the confines of what the law permits or requires. Regardless of the synonym used, the phrase refers to someone who is acting within the boundaries of the law.