Michael Howard says that journalists should not be "cowed" by the findings of the Hutton Report.
Michael Howard tells reporters to be fair but rigorous
The Conservative leader told journalists at an award ceremony to continue to "challenge politicians".
He said that, while he accepted Lord Hutton's report, journalists should not be "intimidated".
He went on to pay tribute to former BBC director general, Greg Dyke, and chairman, Gavyn Davies, saying their resignations were "honourable".
Mr Howard, attending a local journalism award ceremony in Faversham, Kent, told reporters: "It is vital that you are not cowed, and that you carry out your responsibilities fairly but rigorously."
"One of your roles is indeed to challenge politicians," he said.
"Of course, allegations of a lack of integrity should not become routine ... but there will be occasions when such allegations are appropriate."
"And when they are, you must be free to make them and must not be intimidated from doing so," he said.
"The fact that Lord Hutton had come to some conclusions over specific issues does not mean we need to change our behaviour."
Mr Howard also called for an official inquiry into the intelligence material that led the country to war.
"A number of questions have been raised, and it is right and proper that that should be looked at," he said.