Civil service impartiality will be discussed at the TUC
As a trade union prepared to attack the "creeping politicisation" of Whitehall, Labour MP Tony Wright said it would be appalling if Britain did not get a Civil Service act.
The association, which represents 11,000 government officials, argues that a process of politicisation that began under the Conservatives has continued under Labour.
'Impossible not to legislate'
Dr Wright chairs the all-party Commons public administration select committee, which called for action on the issue earlier this year.
"The demarcation lines have to be transparent and properly policed," he told BBC Radio 4's The World At One.
"I think we've reached a point now where it's impossible not to legislate.
"It's now politically embarrassing and in some sense shameful that we haven't had a Civil Service act.
"The assumption is that there will be legislation and I think it would be appalling if there was not."
FDA general secretary Jonathan Baume said there was a "slow process" which was seeing the work of civil servants moving "into more political directions".
Effectively some civil servants were being put into a situation where they were expected to promote rather than explain policy, Mr Baume said.
Impartial history
Britain's reliance on an impartial Civil Service dated back some 150 years and government, as well as opposition, would be strengthened by legislation to reinforce that impartiality, he said.
"We do see this as being an important measure during a period of great constitutional change."
The motion attacks "the growing trend for the government of the day to use senior civil servants as direct representatives on their behalf, in turn making it more difficult for civil servants to fulfil their role in offering independent and impartial advice".
One of the factors prompting the move is the number of special advisors and political appointees brought in to Whitehall in recent years.
Arms being twisted
Liberal Democrat home affairs spokesman Norman Baker said the union was right to express concern about the politicisation of the civil service.
"Labour must be prevented from bringing the Civil Service into disrepute," he said.
"They are twisting the arm of the civil service to behave as a department of the Labour Party."
A spokesman for the Cabinet Office said the government was committed to both maintaining a "non-political permanent civil service" and to legislating on Whitehall when there was a suitable opportunity in its busy legislative programme.
"In the meantime... the civil service code and other documents set out very clearly for parliament and the public the framework on the way the civil service works."