Regina MP Erin Weir has decided not to run for re-election, saying the decision comes after his unsuccessful efforts to resolve his expulsion from the NDP caucus.

"Unfortunately, the federal NDP leader has refused to take a second look at a deeply flawed process or to allow local NDP members to nominate their own candidate, and so for that reason, I will not run in this year's federal election," he said.

Weir said he was proud of the work he had done as the MP for Regina-Lewvan over the last term, saying the riding association has also doubled its membership and bank account in that time.

"I believe the best chance to maintain progressive representation in the constituency would be to build upon that work. Unfortunately, a new NDP candidate is going to have to go back to square one."

Weir has been sitting as an independent since May 2018 when he was expelled from the NDP caucus following a third-party investigation into harassment and sexual harassment complaints.

It was alleged Weir argued with a staffer excessively and stood too close when speaking to people.

There's no question I think that will detract from his popularity and electoral chances. - NDP Erin Weir on federal leader Jagmeet Singh

Weir said he's had a "tremendous outpouring of sympathy and support" from constituents and others who believe there was a lack of due process in NDP leader Jagmeet Singh's decision to investigate and expel him.

"There's no question I think that will detract from his popularity and electoral chances," Weir said, adding that in his own riding, he believes the Conservatives will pose a "huge threat" to the NDP.

A letter signed by a group of 68 former NDP MPs and MLAs have criticized Singh's handling of Weir's expulsion, accusing him of flouting proper procedure and acting on "hearsay." It said Weir had sufficiently convinced his trainer that he now "gets it" and had made efforts to apologize and make amends to those affected by his actions.

There has not yet been a NDP candidate nominated in the Regina-Lewvan area, with Weir saying he believes that the party has only nominated candidates in three out of 14 ridings in Saskatchewan.

"I do think the current NDP federal leader has failed to articulate clear positions on a wide range of public policy issues, including some that are extremely important to Saskatchewan," he said.

He said there needs to be more clarity on the party's stance on oil pipelines and carbon pricing, the latter which he describes as potentially "the most significant policy debate" in the next election.

CBC News has reached out to the federal NDP for a response to Weir's decision not to run and to his concerns.

NDP Leader Jagmeet Singh has previously said he stood firm on his decision to expel Weir, and that it was important to ensure a safe workplace. (Darryl Dyck/Canadian Press)

Singh has said in the past that he stood by his decision to expel Weir, despite some people trying to intimidate him to change that decision.

"I think it is very important that we take a stand, that I take a stand as leader to make sure that we ensure, that I ensure, a safe workplace," Singh said in September.

A 'generational divide' on controversy, says prof

Jim Farney, who heads up the University of Regina's Politics and International Studies department, said he perceives there to be a mixed reaction to Weir's expulsion.

"There's a clear generational divide," Farney said. "It's mostly older people who are supporting him in the party and a lot of the younger activists are quite upset with him — they buy Singh's position."

Jim Farney, a professor with the University of Regina's Politics and International Studies department, says he believes Weir's political future is likely over after allegations of harassment saw him expelled from the NDP caucus. (CBC)

Even still, the NDP has been struggling to win the fight to be progressive Canadians' voice and has done little to advance its cause in Saskatchewan, he said.

So far, the Green Party has declared Naomi Hunter as its candidate in Regina-Lewvan, while Saskatchewan Party MLA Warren Steinley won the Conservative nomination last April.

Steinley has had a year-long head-start in wooing voters, Farney pointed out.

"I think it's an uphill battle for whoever wins the NDP or Liberal nomination," Farney said.

The federal election is on October 21.

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