MP 'naive' to discuss WA top cop job

A new Labor backbencher was politically naive when he voiced his opinion about the selection process of Western Australia's new police commissioner, the premier says.

The process has been shrouded in controversy after former Australian Federal Police commissioner Mick Keelty withdrew from the committee citing unavailability for interviews due to overseas travel.

There were also claims of political interference after Labor backbencher and ex-policeman Mark Folkard reportedly questioned why a former colleague was not granted a final interview.

Premier Mark McGowan said Mr Folkard had been politically naive and he had counselled the Burns Beach member.

"He had views about the issue, he passed it on to me, I didn't take it any further," Mr McGowan told reporters on Tuesday.

"He's very enthusiastic. I think he's learnt a lesson."

Police Minister Michelle Roberts denied on Monday that there had been political interference in the process after the opposition and WA Police Union expressed concern.

Mr Keelty has been replaced by former Victoria Police chief commissioner Ken Lay, who joins Mal Wauchope, Kay Hallahan and Robert Mitchell, with interviews to be held in mid-July.

Asked why the list of interviewees had increased from six to 10, Mr McGowan said everything was "completely above board" and the Public Sector Commission just wanted to have the biggest field available.

He denied it was a case of anyone being removed and re-added to the list.

But the premier could not explain why Mr Keelty's scheduling conflict was not determined earlier.

"People have diary conflicts all the time," he said.

"You can't do the interviews by Skype, so that's unavoidable."

Police Commissioner Karl O'Callaghan is due to leave in August after 13 years.

Among his possible replacements are NSW deputy police commissioner Catherine Burn and Australian Criminal Intelligence Commission chief Chris Dawson.