The police chief at the centre of a row over the shooting of an unarmed man resigned on Tuesday.

Just one day after the intervention of the home secretary, Paul Whitehouse stepped down claiming he has been "unjustly vilified".

David Blunkett has welcomed the move and expressed his support for the local police authority's efforts "to secure the maintenance of efficient and effective policing".

"I respect the decision of Paul Whitehouse to stand down as chief constable of Sussex and believe that this is in the best interests of the force and the people of Sussex," he said.

Whitehouse provoked a storm when he backed the promotions and back-dated pay rises of two police officers involved in a bungled armed drugs raid that left an unarmed man dead.

The Sussex police officers had been savaged by a series of police investigations into the shooting of James Ashley in January 1998. He was shot dead, after being woken, unarmed and standing naked in his bedroom.

Five police officers were charged with the killing but were acquitted of any criminal offence. Blunkett described the incident as giving "rise to grave public concern".

In an unprecedented step, indicating a new more direct and confrontational approach to the police by the newly appointed home secretary, Blunkett piled pressure on the local police authority to consider sacking Whitehouse. "I expect the police authority to take whatever steps are necessary to restore public confidence and to ensure that the force has learned the lessons from this incident.

"There are statutory powers available to me as home secretary. They include powers under section 49 of the Police Act 1996. to require the police authority to exercise its powers under section 11 to call upon the chief constable to retire in the interests of efficiency or effectiveness.

"I expect the police authority to do whatever is necessary to fulfil that statutory duty, and consider the full range of statutory powers which are available to it, including whether the police authority believes that it would be right to use its powers to require the chief constable to step down," he said.

Blunkett is set to meet the Liverpool family of Ashley to discuss the possibility of a public inquiry in to the shooting.

His two children are set to sue the police and may take the case to the European Court of Human Rights.

On Monday morning the Sussex police authority issued a statement announcing the resignation and stating that Whitehouse would stay in post until September 25.

"Arrangements will be put in hand to appoint his successor. The police authority will continue to work with and support the force in providing policing in Sussex," said the statement.

Whitehouse turned on a fellow senior police officer who had conducted the investigation, but has yet to report, in to the killing - a team of officers from Kent County Constabulary, led by deputy assistant commissioner Barbara Wilding.

"I don't know for what reason she wrote the report in the way she did. If I know the motives behind the way the reports were written and the way the investigations were carried out, I would be much happier. None of my colleagues understand it," he said.

Another investigation by respected former Hampshire chief constable Sir John Hoddinot accused Whitehouse of issuing a "disingenuous'" press release following the killing which over-stated the danger posed by Ashley.

It accused him of maintaining the argument that his officers had behaved properly despite contrary evidence. Sir John's report found evidence of criminal misfeasance - or wilful neglect of duty - by Whitehouse, the deputy chief constable Mark Jordan, who remains suspended, and assistant chief constable Nigel Yeo.

Whitehouse has also questioned Blunkett's judgement and manners. "If society at large wishes us to deal with people who deal in drugs and happen to be armed, then police officers are going to have to be armed, or we will never be able to deal with drug dealers. Mr Blunkett has got to make a choice there," he said.

In an open letter, Whitehouse expressed regret for Ashley's death and further spelt out his criticism of investigations in to the shooting.

"Unfortunately it would seem from leaks of confidential reports made in the course of the investigations the whole truth has not been reported. In addition those officers who were involved in the operation have been unjustly vilified. I do not understand the motive for it and I am saddened by it. I hope that the officers involved will get the opportunity to put their side of events and they will continue to have my full support," he said.

His departure has been welcomed by Liverpool MP Louise Ellman, who highlighted the police killings of 15 unarmed people in the last decade and welcomed Blunkett's intervention.

"Despite severe condemnation of the planning and execution of the fatal raid, no-one has been found responsible. Now officers involved have been promoted. I very much welcome the intervention of the home secretary and the subsequent resignation of the chief constable," she said.

"The Ashley case raises major issues about responsibility and accountability in the use of firearms by police. It is the tip of the iceberg. David Blunkett's decisive intervention in this case is a very significant first step in attending to these critical issues."

The most recent statistics on the police use of firearms were given in a parliamentary answer to Labour MP, Phil Hope, in April last year.

The figures between April 1998 to March 1999 revealed the number of police operations involving the issue of firearms to be 10,928 - down seven per cent on the previous year. The impact of the Ashley on the Sussex police's use of firearms was striking, with use down by almost two thirds - from 330 to 123 instances.

But the number of shootings in England and Wales rose from three to five - without fatalities. The use of firearms by the Metropolitan police continues to rise.

The creation of a new independent system for dealing with police complaints, the Independent Police Complaints Commission was announced in the Queens speech, a move welcomed by human rights campaigners Liberty.

"The James Ashley case is the latest in a series of fatal shootings where there have been criticisms of the police investigation, the prosecution and disciplinary processes. The new IPCC needs to be truly independent of the police, with sufficient powers and resources to carry out its own investigations, prosecutions, and present disciplinary charges.

"Unless this occurs public confidence in the ability of the system to deal with police misconduct will remain low, and friends and relatives of victims will continue to feel that they have not received justice," said Liberty director, John Wadham.