Alberta Education Minister Thomas Lukaszuk alleges he was hit by a voter while door-knocking, though the resident claims he simply steered the minister off his property. Police are investigating.
Redford told reporters Monday she is concerned about fear and anger taking hold during the campaign.
"It's absolutely fine for people to have differences of opinion. But for people to have been so emotional and so worked up that that happened is really unfortunate," Redford said while making an campaign announcement in Beiseker, near Calgary.
"I don't think that's the way we want politics in Alberta to be, and hopefully we'll all take a step back and think about behaviour again."
Lukaszuk was door-knocking in his Edmonton Castle-Downs constituency when the confrontation happened Saturday afternoon.
He alleges a man who opened his front door swore at him, ordered him off his property and punched him. Lukaszuk later called police.
"As a person I forgive him, because it's obvious he has issues with managing his anger," said Lukaszuk.
But he said reporting the incident to police was the right thing to do. As education minister, he has worked hard to stop bullying in schools.
"Whether it's in a schoolyard or whether it's in our neighbourhood, that's how we deal with bullies," he said.
Wildrose Leader Danielle Smith and Liberal Leader Raj Sherman both refused to comment on the case. But they agreed that if someone doesn't want to talk politics, candidates need to walk away.
"What we will tell our candidates is that if somebody asks you to leave the doorstep, you should politely leave and move on to the next door," Smith said.
Al Michalchuk, 67, said he repeatedly asked Lukaszuk to leave but insists he never punched him. He said he grabbed the candidate's arm to turn him around, then put his hand on his back.
Michalchuk said he expects police may charge him with assault, but two criminal defence lawyers have already offered to represent him if that happens.
He has given police footage from a video surveillance camera at his home. Although the video does not show the altercation, it shows Michalchuk from behind at his front door moving his arms.
The retired businessman said he is waiting to have surgery on his knee and shoulder and is dying of liver failure.
"Do I look like somebody that can take a round out of a man like that? Really?"
Michalchuk said he was a die-hard Conservative but has been recently turned off by what he says is the arrogance of the party. Although there's a Wildrose sign on his front lawn, he said he likely won't be voting for them either.
He said a Wildrose volunteer was putting a sign up at the house next door, so he agreed to have one put on his property too.
"I'm undecided right now," Michalchuk said. "I want see to see the debate."
Party leaders go head-to-head during a televised debate Thursday night.
Voters head to the polls April 23.
— With files from Chris Purdy in Edmonton
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