Up until last March, Montgomery was a justice reporter with the Montreal Gazette.
She was one of five journalists who accepted a buyout package from Postmedia, the Gazette's parent company, last winter.
"Many Canadians are fed up with the Harper regime and the Liberals are not a viable option," said Montgomery.
"I can no longer sit back and watch."
Montgomery has covered many elections over the course of her 30-year career in journalism.
She says she's not worried about being on the other side of the podium and her experience will make her a "straight-talking" candidate.
Montgomery gained national attention when she and a colleague started the social media hashtag #beenrapedneverreported.
The hashtag was started to open up a dialogue among sexual assault survivors after several women came forward with previously unreported allegations of assault and sexual assault involving former CBC host Jian Ghomeshi.
Montgomery says she would like to continue the work that was started with #beenrapedneverreported if elected as an MP.
She said her priorities also include the environment and re-establishing Canada's reputation on the international stage.
Candidates for the NDP nomination in NDG-Westmount are still coming forward. Montgomery says there are at least seven other people seeking the same nomination.
Newly redrawn riding
One of those candidates is current Côte-des-Neiges—Notre-Dame-de-Grâce city councillor Peter McQueen.
The chosen NDP candidate will be up against a significant opponent: Liberal incumbent Marc Garneau.
Garneau is the sitting MP in the Westmount-Ville-Marie riding. That riding will cease to exist following the next election. The area will be served by two ridings: NDG-Westmount and Ville-Marie–Le Sud-Ouest–Île-des-Sœurs.
Garneau was acclaimed as the Liberal candidate in NDG-Westmount last year.
"I like Marc Garneau. He's a good politician," Montgomery said.
"But it's time for him to move on and make way for new ideas and new blood."
Sue Montgomery will be live in the Daybreak studio Tuesday at 6:40 a.m. ET. Listen to her interview live here.