Green MP Golriz Ghahraman is stepping down from Parliament after being accused of shoplifting on three separate occasions.

In a statement, Ghahraman said stress relating to her work had led her to "act in ways that are completely out of character. I am not trying to excuse my actions, but I do want to explain them".

"The mental health professional I see says my recent behaviour is consistent with recent events giving rise to extreme stress response, and relating to previously unrecognised trauma," she said.

She said she had fallen short of the high standards expected of elected representatives, and apologised.

"I have let down a lot of people and I am very sorry," the statement said. "It's not a behaviour I can explain because it's not rational in any way, and after medical evaluation, I understand I'm not well.

"The best thing for my mental health is to resign as a Member of Parliament and to focus on my recovery and to find other ways to work for positive change in the world."

Green Party co-leaders Marama Davidson and James Shaw, in a separate statement, said Ghahraman had been the leading voice in Parliament for human rights, truly independent foreign policy, and electoral reform for six years, but "it is clear to us that Ms Ghahraman is in a state of extreme distress".

"She has taken responsibility and apologised. We support the decision she has made to resign.

"We are deeply sorry to see Ms Ghahraman leave under these circumstances and we wish her all the best for the future."

They said she had worked tirelessly on behalf of her communities.

"Nothing detracts from that work and we know she will continue to support those communities in future. We cannot comment on the details of allegations while police investigations are continuing."

Ghahraman also thanked Scotties Boutique "for the kindness and empathy they have shown me", and asked for space and privacy so she could get better.

The allegations involved Auckland clothing retailer Scotties Boutique and Wellington clothing store Cre8iveworx.

Police confirmed they were investigating reports of an incident on 23 December. Police repeatedly refused to comment on any second alleged incident.

Last week, the Greens announced Ghahraman had stood down from all her portfolio responsibilities.

More to come...

This story was originally published by RNZ