Again, it depends on the circumstances which resulted in a DUI. And, being charged with a DUI doesn't necessarily mean that you will be booted out of the military. I remember a First Class who was convicted of a DUI while I was stationed with VFA-131 (had to do the paperwork on it as I was in Personnel) and he only ended up going to Captain's Mast, served 45 days restriction, with a suspended forfeiture of pay, suspended bust (both for 6 months) and was kept in. If he would have messed up and gotten another DUI, then he may have ended up getting booted, but as far as I know, that was his only conviction, and he served until he retired.