I have been in law enforcement for 27 years and the last 12 as a pilot flying full time. For me it has been the best of both worlds. Sure I am not flying turbines (I fly fixed wing not helos) but my QOL is better than almost any airline pilot. My commute is 20 minutes and home every night. I grew up while my mom worked for the airlines and it is not what it used to be. However, neither is law enforcement.
I think that most dept's would require you to work patrol for several years and that is not for most people. I loved it but it can be difficult due to some of the things that you have to see and deal with. Remember that all of the worst stories you see on TV, some Officer had to respond to and investigate. It can be pretty ugly and that can take a toll on your QOL.
The flying can be very challanging. I normally fly by myself and work all of the radios (we have 7 radios) while maneuvering at 500 agl and low speeds keeping track of units and/or suspects, other aircraft, towers, etc. It's great! Most depts will also want you you have all your ratings before begining training. So count on spending at least another $15K if not rated in helos.
I would recommend it also because if you were to lose your medical your still have a job in law enforcement. If you get serious check several depts. They are all different and some are probably not what you think. The federal agencies generally do not do much law enforcement once in an air unit. This may be more appealing to those that don't like that aspect but for me the law enforcement is the best part. Once you are comfortable/competent in the aircraft the action is happening outide of the cockpit.
I am very happy that I did not go the airline route. Although the aircraft are faster, more complex and carry more prestige (to some) it is boring flying. Don't get me wrong everything becomes a job after awhile but mine is generally different every day. You could not give me an airline job today (or tomorrow).
Good luck.