The Green Party says unions are to thank for workplace rights Kiwis now see as a given. 

Co-leader Marama Davidson's announced a members bill to make union membership the default, which is also a Party election policy. 

Membership would still be optional, but workers would need to opt-out, not in.

Newstalk ZB senior political correspondent Barry Soper says this proposal feels like a step backwards, given which other countries have compulsory unions. 

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