The government is facing calls to set up a public register of the Australian offenders being deported here.

A man who killed his girlfriend and dumped her body in a bin is understood to be among 12 deportees who arrived here on Thursday.

Prime Minister John Key won't confirm if the man was on board, but said the government has introduced the best protections it possibly can.

But Sensible Sentencing Trust spokesman Garth McVicar said the public deserve to know who's being deported here.

"When you've got a government playing games with a serious situation, I think we have a major problem about to burst on our shores really."

McVicar said the names and criminal records of the offenders should be published.

He will be under parole-like supervision, under a new law passed under urgency on Wednesday afternoon - but McVicar doesn't believe that's enough.

"The current legislation that's been passed, even though it's subject to review, I can't see that keeping New Zealanders safe, I can't see it doing the job."