Atwell hadn't spoken publicly since Monday morning when the Times Colonist newspaper reported Saanich police responded to a disturbance involving Atwell at the home of one of his campaign workers.
On Wednesday he told reporters staying silent for two days was a mistake, saying the incident had been "blown out of proportion" and media reports were erroneous.
Atwell said on the night of Dec. 11 around 8 p.m. PT he had been invited by a close friend and campaign volunteer to visit her home.
But her partner, who was home at the time, apparently didn't want him there, he said.
"There were voices raised, and I decided it was time to get out of there and walk out, and that's what I did. Unfortunately there was an altercation on the steps," he said.
The mayor said as he was exiting the house he was struck from behind, so he called 911 to ensure everyone's safety.
He said he decided not to press charges and considered the matter over.
'I'm kind of naive I guess'
Atwell said he regretted not speaking to the media sooner to end speculation about his relationship with the woman, which he said was not sexual.
"Well, I guess it gives the impression that there's something really going on and I'm hiding it from it," he said.
"I'm new as a politician, I'm newly minted, I'm kind of naive I guess in my original belief that I thought I had a private life and this was just a very small private episode between three people."
Saanich Police say no charges will be filed against anyone involved, and the file is closed.
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