I agree the age limit could be lowered possibly, but there should be a limit. If you have ever played on a different life server, you've seen the 12 year old cops. It's absolutely ridiculous. The powertrip on those little kids is no joke. As sneaky said, it's impossible to detect maturity within an application, and what Olivia said during a ride along. Hence why an age limit is usually a good way to weed them out. Sure, a few 14 year olds are extremely mature, but at the cost of how many aren't, it's a good system.
And if it were to be lowered, maybe just to 16 or 15. I know many 16/15 year olds who are extremely mature.