Don Russell, sacked as secretary of the Industry Department in one of the Abbott government's first acts, said the public service must reclaim its place in government decision-making.

Do you know more? Send your confidential tips to ps@canberratimes.com.au

Dr Russell said his former colleagues at the top of the public service were to blame for being locked out of the process. He said departmental secretaries had allowed the rot to set in and were responsible for fixing the problem.

Dr Russell, one of several victims of the Coalition's ''night of the short knives'' in September, told an audience in Canberra on Monday evening that it was now common for government decisions to be taken in ministers' offices, with the relevant departments reduced to bystanders.

''Such a dishevelled approach makes governments look untidy and confused,'' Dr Russell said. ''But, more importantly, it stops governments achieving the outcomes they want - they make decisions without all the information and without fully understanding the consequences.

''It may seem harsh but much responsibility for this unfortunate situation lies with departmental secretaries.''

Dr Russell's talk at the Australian National University's Crawford School of Public Policy was the first public appearance of any of the victims of September's purge of senior officials.

Andrew Metcalfe was sacked from the Department of Agriculture and Blair Comley bundled out of the Resources Department. On the same day, the director-general of AusAID, Peter Baxter, went on ''extended leave'' just hours before the abolition of his agency was made public and Treasury secretary Martin Parkinson agreed to step down midyear.

On Monday, Dr Russell offered Prime Minister Tony Abbott some advice - he should rely more on the public service if he was to build a proud political legacy.

''What is needed is sophisticated and well-considered decision-making,'' Dr Russell said. ''Ministers and prime ministers should have the wisdom to appreciate that nobody builds a respected legacy on the back of a confused collection of reactive press releases and disjointed policy announcements.

''Politics is a relative profession - you only have to be better than your opponent - but a legacy is absolute.

''All political careers end badly and to answer the question 'what did it all mean?' you have to have done things that left the nation a better place.''

But nothing would change until the men and women who run the public service flex their muscles, Dr Russell warned.

''Secretaries have more authority than they think,'' he said.

''They can build imaginative institutions that ministers want to consult and they themselves can be effective advocates, encouraging their ministers to do sensible things that are good for the minister and good for the nation.

''At the risk of feeding the cult of the secretary, I can say that only the secretaries can save the APS.

''But, at the end of the day, prime ministers determine how government runs in Canberra.''