A Greens candidate in the Victorian election has quit over comments she said were made "in jest" about shoplifting.

Key points: Candidate says she does not want to be "a distraction" for the Greens

Candidate says she does not want to be "a distraction" for the Greens Party accepts resignation, says Ms Nilson has "done the right thing"

Party accepts resignation, says Ms Nilson has "done the right thing" Liberal MP says Greens should vet candidates more thoroughly

The comments were made in a secret Facebook group called "Bad Gals Club", and included tips on how to shoplift, as well as derogatory comments about a female Liberal senator.

Ms Nilson — who was a candidate for the Upper House in the Northern Metropolitan Region — deactivated her Facebook account after she was asked about the comments by the Herald Sun newspaper.

Ms Nilson said she had decided to withdraw from the race because she did not want the comments to be a distraction for the Greens.

"I regret making these comments," Ms Nilson said in a statement.

"While they were made several years ago, in jest online, and are in no way reflective of my beliefs or actions, I don't want them to be a distraction.

"I have resigned as a candidate, and the party has accepted my resignation."

A Greens spokesperson confirmed her resignation.

"Joanna regrets making these comments and has done the right thing by resigning as to not distract from the campaign," the spokesperson said.

Coalition criticises candidate vetting

Liberal shadow treasurer Michael O'Brien said the posts show Ms Nilson is not "suitable for parliament".

"I think if somebody is there not only boasting about stealing, but actually providing instruction on how to do it, I don't think that qualifies as a joke," he said.

"Since the Greens … want to be in a power sharing arrangement with Labor I think that those parties have got a greater responsibility to ensure their candidates are fit and proper people and they're properly vetted."

Victorian Greens leader Samantha Ratnam rejected suggestions the party's vetting process was not thorough enough.

"Look, we're disappointed with what's occurred," she said.

"We have vetting and probity processes and this has come to light post that process … this does happen in election campaigns to a number and range of parties as well.

"That being said, when the matter came to light she took full responsibility, she's apologised and she has withdrawn her candidacy."

Preference deals still being wrangled

The Greens are mounting a serious challenge against Labor in the inner city seats of Brunswick, Albert Park and Richmond.

They already hold Melbourne, Northcote and Prahran, and picking up additional seats could put them in a position of holding the balance of power in the next Parliament.

Today the party revealed it would attempt to use any balance of power to push for improved disability access standards around public transport and private housing.

Asked about preference deals with the major parties, Dr Ratnam said voters could make up their own minds, but negotiations were underway.

"The Greens have always preferenced progressives over conservatives," she said.

"We encourage individual voters to make up their own minds about who they preference. Decisions around preference negotiations are still [ongoing]."

The Liberals are yet to confirm whether they will run candidates in the inner-city seats at risk of falling to the Greens, but Opposition leader Matthew Guy said a decision would be made soon.

There is also speculation the Liberals may run an open ticket, not directing their supporters to put the Greens last and increasing the chances of Labor losses.

Mr Guy was coy on the subject.

"We'll make a straightforward decision on this in a week or so when the administrative committee meets on this matter," he said.