Talk about swift justice ... boxer Vinny Paz already had his day in court after being arrested for domestic violence Thursday morning ... and he got off relatively easy -- avoiding any jail time.
Paz was arrested this morning in Rhode Island after cops say V.P. refused to exit his house after allegedly beating up his GF ... forcing cops to bust down his garage door.
Less than 10 hours after being charged with 2 misdemeanor domestic violence counts -- Paz appeared in front of a judge and immediately copped a plea ... pleading no contest to domestic violence simple assault.
The other charge was dismissed.
Paz won't spend time behind bars ... but he ain't free and clear. The judge ordered him to take domestic abuse and substance abuse counseling, participate in a mental health program, and give up his guns.
He's also on probation for a year ... and isn't allowed to contact the victim for a year.