Democrat Jim Prendergast says he is telling voters about his 1996 misdemeanor assault conviction "to be honest with the people I'm going to work for."
He also says he wants to explain the arrest on his terms, rather than have his opponent bring it up in an attack ad.
Prendergast calls the incident a turning point in his life. He says he didn't strike his then-wife, but grabbed her roughly with both hands during an argument.
He says he and his ex-wife are now on friendly terms.
The man he's running to unseat, Republican state Rep. Tom Quigley, says he never had any intention of bringing up the incident.