So there is no crime? There just happens to be a lot of people who do this.
It may not ever be prosecuted, but it is a crime. And such action can show a great deal of immaturity.
How old are you now, and what have you done since this childish high school affair to show that you are now mature and responsible? The actions you describe are unlikely to prevent you from getting a job in law enforcement, but if you attempt to conceal it and it gets out that you did this, then you can kiss a career goodbye. best to be up front with any background investigator. Frankly, if you brought it up with me in a background investigation and you have been out of high school a few years, I'd make a small footnote, but it would pretty much be a non-issue unless such immature actions have continued.