"It was a misdemeanor, he served his probation, and he's not a registered sex offender," Hardy said. "His issue has nothing to do with me or my candidacy."
The mailer accuses Hardy of favoring her brother over children when she voted while on the council against endorsing Jessica's Law, which prohibits sex offenders from living near schools or parks.
Hardy said her vote had nothing to do with her brother, who wouldn't have been affected by the law. She said she voted no at the advice of law enforcement officers who said it would lead sex offenders to become homeless and make it harder for police to track them.
Only the state's more serious sex offenders must register their locations with police and appear on the Megan's Law website.
Emails and phone calls to Atlas and Chairman Lee Lowrey were not returned.
Atlas also accused Hardy of having "a troubling record of hurting kids."
And on Wednesday, another Atlas mailer claimed Hardy had to resign her post from the Huntington Beach Union School District for endangering a Huntington Beach High School student on a school trip to Moscow.
According to Atlas, she left the student unattended on a bus, leading another student to call paramedics.
Hardy said an 18-year-old student on the trip merely fell ill with the flu and was taken care of by a male advisor in accordance with the school district's policy. Hardy noted that the male advisor was the one who called paramedics.
Hardy was not forced to resign by the district, she said. She now teaches math and social studies at another Union school, Marina High School.
The PAC has endorsed Councilman Devin Dwyer, who is the only incumbent in the race, Planning Commissioner Erik Peterson and former Mayor Dave Sullivan, who is running for the third time.
Hardy does not blame them for the hit pieces, saying none of them controls the PAC's activities.