Just so you know I speak from experience...I started out with the Cook Co Sheriff's Office, working the jail and was part-time with a suburban Chicago PD. Then I worked for the Chicago Housing Authority PD. Then Chicago PD. Now I work for a large Metro PD in Arizona.
I love the work, but I hate the job. Sometimes I hate the work too. Law enforcement is nothing like you imagine...even if you have close family and friends giving you the inside scoop.
I've gone through career burn-out twice, lost one partner and a few friends in the line of duty and a marriage. I've worked patrol, homicide, dope, gangs, auto-theft and swat.
I guess it really depends on the kind of agency you work for, but dealing with human garbage day-in and day-out really starts to dim your view of society in general.
Carefully research the PDs you want to work for. Try to do a couple of ride-alongs with each of them. It can be a very difficult job at times...ok..MOST of the time, difficult in the sense of being frustrated with the idiots in Admin around you and some of your fellow officers.
I'm sure there are other coppers out there who still love the job every day and love the place they work in, so don't let my little black cloud sour you out of it.
In short, if you want to do it, go for it. You will regret it for the rest of your life if it's really something you want to do.
ETA: We had a guy in our last recruit class who is 42. After a couple of eye-openers, he's turning out to be a very good street officer.
Sheep