I've only known one cop who decided to go to law school, and quit after 1L summer. Once she got a taste of what she would be doing as a lawyer, she realized she would be going from a career where she does a lot of paperwork because of stupid people to a career where she'd be doing an even greater amount of paperwork because of stupid people.
But if you really want to do it, your age and your previous career will neither help nor hinder your admission to law school. It's almost all in the numbers. Though I'm sure you'll be able to come up with a pretty compelling personal statement to go with your applications.