TMZ broke the story ... Simpson was popped at a DUI checkpoint in Sherman Oaks, CA earlier this month ... and blew .12 on the breathalyzer test.
Now, we've learned ... the L.A. City Attorney has filed 2 misdemeanor counts of driving under the influence against Papa Joe ... which carry a maximum sentence of 6 months in jail.
If convicted on both counts, Joe COULD face up to 36 months probation and a $1,000 fine -- but as a first-time offender, it's highly unlikely he'll end up behind bars. He'll probably end up with a fine and probation.
Joe's case is scheduled to go before the judge later this month.