A former Green MP says he's baffled the party hasn't ruled out using waka-jumping laws against Darleen Tana.

The party has Tana to resign as an MP, after receiving a report on her knowledge of alleged migrant exploitation at her husband's business.

Tana has quit the Green Party, but says she doesn't accept the report findings.

The Greens previously opposed laws that would now let them formally request Tana's removal from Parliament.

Former MP Gareth Hughes says he'd be very surprised it they changed their stance.

"It would be a huge departure for the Greens to use it, given their decades-long opposition to it under multiple leaders, multiple caucuses - they haven't used it in the past."

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