Cheshire's police commissioner has blamed investigators he appointed for "shortcomings" in the probe into bullying allegations against the county's former chief constable.
Simon Byrne was cleared of all charges last December.
A misconduct panel found the process "could and should have been avoided".
Commissioner David Keane told councillors the investigation into the allegations by North Yorkshire Police officers was "sub optimal".
Mr Byrne was suspended in August 2017 but his contract with the force expired in June 2018, while he was waiting for his hearing to be held.
Mr Keane was questioned by councillors about his decision to bring charges of gross misconduct, which Mr Byrne said had been "an ordeal" that "wasted precious public money".
The Labour commissioner told Cheshire's police and crime panel it would be "improper to ignore a series of complaints from officers and staff".
He said it was a "problem" that the North Yorkshire investigators did not interview Mr Keane, and had "applied the wrong test" when assessing whether the allegations amounted to gross misconduct.
"I would be the first to recognise how time-consuming and costly this has been", he added.
But he said the £421,000 cost had been "dictated by a process laid down by the government".
Conservative police and crime panel member Andrew Dawson said the commissioner had been unable to "manage the process effectively" while independent member Evan Morris said he had "abrogated all responsibility".