Mary Lou McDonald has refused to apologise for comments about who the next head of the PSNI should be.
The Sinn Féin leader has called for an outsider to be the next boss of the Northern Irish police force.
She said she doesn't have confidence in any of the current leadership team to replace George Hamilton when he steps down later this year.
Her remarks led to the Police Federation of Northern Ireland calling for an apology from the Sinn Féin leader.
The federation's chair Mark Lindsay claimed: "This amounts to extraordinary interference in an open and transparent selection process.
"Sinn Féin’s representatives on the Northern Ireland Policing Board will have a role to play in deciding on Mr Hamilton’s successor.
"To adopt this public position now is wholly inappropriate, offensive and ill-judged."
A number of Northern Irish politicians also raised concerns about the remarks, including John Blair of the Alliance Party.
He called it a "careless and irresponsible thing to say".
— Alliance Party (@allianceparty) February 18, 2019
The DUP, meanwhile, said it was seeking 'legal advice' following the statement.
'No credibility in terms of dealing with legacy'
Speaking this afternoon, Mary Lou McDonald stuck by her stance.
She said: "Any comments that I have made, be very clear, are reflective of exasperation and real worry and real upset from real people who live up the road.
"Any comments I will ever make will be in the interests of delivering credible policing services that people can support."
Deputy McDonald added: "The PSNI have no credibility in terms of dealing with legacy.
"They are repeat offenders in terms of not providing information: not just to the ombudsman, but to the coroners and so on... I've said this to the PSNI."
George Hamilton last month announced his intention to retire as chief constable in June.
He's been in the role since 2014, and turned down the offer of a three-year extension to his contract.