City archivist Rita Freedman has been disciplined for alerting councillors to plans to move historical records out of the city centre.
City of York Council has issued her with a written warning for insubordination after she wrote to every member saying that discussions were taking place about moving the city archives to the University of York.
UNISON today warned the council that it will treat the warning as victimisation, and is prepared to take legal action under the Public Interest Disclosures Act - the law drawn up to protect whistleblowers.
York convenor Peter Household said: "There is a strong likelihood that we will be seeking a legal remedy if the warning isn't withdrawn."
He said the process would probably be an appeal to a panel of councillors which, if unsuccessful, would be followed by a legal tribunal.
"This warning is unacceptable to UNISON and we consider that Mrs Freedman is being victimised contrary to the Public Interest Disclosures Act," said Mr Household.
The act states that anyone making a qualified disclosure has the right to protection from discrimination.
Mr Household said Mrs Freedman acted because she felt the council was failing to comply with a legal obligation.
Under rules covering Best Value studies of council departments, any proposals must involve consultation with interested parties.
Mrs Freedman wrote her letter because she feared changes were being discussed without consultation, said Mr Household.
"There is a very strong feeling among union members who are aware of the details that this is absolutely atrocious," he said.
"We feel Mrs Freedman is being victimised for informing councillors who are there to be informed. We feel she was performing her duty."
Mrs Freedman was initially suspended by the council because her "whistle blowing" was seen as insubordination. She was later reinstated.
Charlie Croft, acting head of the York Leisure Office, which covers the archives, said today: "As far as we are concerned, the disciplinary hearing draws a line under the whole matter and it is now a closed issue."
Meanwhile, users of the city archives have formed a group to protect them.
Sarah Costley, of the Friends of York City Archives, said: "We are people who deposit records or use the archives and we want to be represented in any discussions which will affect their future."
Mr Croft has always said there are no proposals to move the archives, although it has been revealed that discussions have taken place about their future.
adam.nichols@ycp.co.uk
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