Parents and governors are to launch legal action to challenge Government plans to force a primary school to be absorbed by an academy chain.

The Department for Education (DfE) wants to remove Roke Primary in Kenley from Croydon Council's control and hand the reins to the Harris Federation instead.

But campaigners have condemned a consultation on the conversion as "a sham" after ministers asked the Federation to run the consultation itself.

They also criticised the consultation questionnaires, which originally did not ask whether parents wanted the school to become an academy at all.

The proposed academy conversion had already provoked anger at the school, with opponents claiming the DfE had flouted its own guidelines by selecting Roke for academy conversion after just one bad Ofsted report.

Governors said say the DfE threatened to fire them if they dissented against the plans. 

A group of parents and governors are now taking advice from solicitors to determine whether the DfE has acted legally, with a view to preparing a challenge to make Michael Gove's department to back down.

It raises the prospect of a potential High Court battle between parents and the Government.

Malcolm Farquharson, chair of governors, said: "The department has behaved appallingly and they have left us little option but to look to see if we can do something legally.

"There really has not been a consultation at all. The DfE has nominated a sponsor and that sponsor is running a consultation. It is a nonsense."

A DfE spokeswoman insisted there was no "done deal" to see Harris become Roke's sponsor. 

She said: "Ministers will carefully consider all responses to the consultation which is due to start soon, before taking a final decision.

"Harris remains our preferred sponsor as they have extensive experience of turning around previously under performing schools in London - nine of which are now judged outstanding by Ofsted."

But the Government's stance has incensed some parents, who said inspectors who visited Roke in January were happy with its progress.

Becky Carrier, 31, whose eight-year-old daughter Millie attends the school, said: "If I thought Roke was failing my daughter, she wouldn't even be there."

Richard Ottaway, Conservative MP for Croydon South, said it was "premature and wrong to force Roke into a partnership with Harris" when it was already improving.

Department for Education policy is designed to ensure schools which are "seriously failing, or unable to improve their results, are transformed through conversion to academy status". 

Roke, in Little Roke Road, received three consecutive "outstanding" ratings from Ofsted before being judged to be inadequate in June 2012. 

The school said the collapse was caused partly by a computer failure which prevented it from sending complete data to inspectors on time.

A monitoring inspection in January found that the school was making satisfactory progress under the guidance of Purley secondary Riddlesdown Collegiate. 

The DfE last year rejected Roke's request to be partnered with Riddlesdown if it was forced to become an academy.

A Harris Federation spokeswoman said: "The consultation meetings last week were well attended, with lots of questions asked and many different points of view expressed. 

"We look forward to seeing the views that are given on the response forms when they come back."

The consultation period will end on April 19.