Mothers Against Drunk Driving unloaded on Stewart over comments he made to TMZ Sports ... in which Rod asked the public to forgive the soccer superstar because "we all make mistakes."

"MADD is appalled the music icon Rod Stewart referred to drunk driving as a mistake," the org. said in a statement.

"While we are relieved that Rooney’s alleged drunk driving killed or injured no one, excuses should never be made for anyone who makes the choice to endanger lives in this manner."

"Drunk driving is a 100% preventable choice, 100% of the time. To say anything to the contrary diminishes the seriousness of the crime and is a smack in the face to drunk driving victims everywhere."

For the record, Rooney was arrested on suspicion of drunk driving early Friday morning but hasn't been convicted.