A Jefferson County judge gave Sherrie Gavan, 54, of Imperial two years of probation Tuesday, The St. Louis Post-Dispatch reported. Judge Timothy Miller told Gavan that does not mean he approves of her action.
"In a vigilante system, there is no justice, only vengeance," Miller said.
If Gavan stays out of trouble for two years, the assault conviction will not stay on her record.
Gavan attacked Jonathan Lloyd after he showed up at the Pizza Hut where she was working in December 2011. She said she was trying desperately to keep her son, Clayton, off heroin, including bringing him to work.
She followed Lloyd back to his house and then hit him with a bat after he walked toward her in what she described as a threatening manner.
Lloyd says he is not a drug dealer. He pleaded guilty recently to drug possession and theft.
Clayton Gavan, now 18, said watching his mother go through the legal system has helped keep him off drugs.