The La Crosse County district attorney’s office says a 22-year-old man involved in a shooting last April on the city’s south side is going to prison.  As a felon, it wasn’t legal for Trevongh Martin to possess a firearm.  Investigators say somebody shot at Martin as he approached an apartment building and he returned their fire before running from the location.  Martin entered a guilty plea Wednesday.  When he gets out of prison, he will be on extended supervision for one year.