Police leading a huge but largely abortive child abuse inquiry denied yesterday they had encouraged false allegations and wrecked the lives of innocent teachers and care workers by "trawling" for evidence in children's homes.

Dozens of professionals in the north-east, backed by MPs, have lodged complaints about the blunderbuss effect of the five-year Operation Rose that saw more than 200 people investigated but in the end only six convicted.

The £5m inquiry led to 558 claims of assault, rape and other sexual abuse from 277 residents or former residents of 61 care homes.

The methods used by Northumbria police have been referred to the Commons home affairs committee, which is studying the handling of hundreds of similar child abuse allegations in care homes.

The scale of the north-east inquiry has emerged with the lifting of a legal gag. The two years of reporting restrictions on the trials of 32 north-east care workers and teachers linked to 142 allegations of child abuse, ended on Tuesday with the collapse of the final case in Newcastle crown court.

The legal move has cleared the way for the complaints of care workers and teachers either acquitted by juries or told by police that they would not face trial.

Ray Johnson, co-chairman of the north-east branch of Falsely Accused Carers and Teachers, said that the clumsy snail's pace investigation had destroyed his life and career as it had scores of others.

He has lodged papers with the police complaints authority claiming malicious prosecution and victimisation after a judge threw out charges against him because a three-and-a-half-year delay had flouted his human rights. "My life has been utterly destroyed for the past five years for no reason whatsoever," he said. "People who abuse children physically or sexually should be punished, but the methods of the Northumbria police have brought the downfall of innocent people whose only crime was to look after disaffected children in homes."

John Scott, assistant chief constable of Northumbria police, defended the idea of the "trawling" system yesterday but acknowledged that it could trap the innocent. He said: "We would conduct the inquiry in the same way, were we to do it again. However, recommendations have been made to establish best practice."

The police have now drawn up recommendations for child abuse inquiries involving care homes, which include "fast track" legal preparation to get cases quickly to court, and a national protocol to record unused material.

There are about 85 cases pending nationally and the Commons committee is studying a further 100 convictions of care workers and teachers dating back 30 years.

The committee chair, Chris Mullin, Labour MP for Sunderland, said in January as the inquiry was set up: "It's been suggested that a new genre of miscarriage of justice has arisen from the over-enthusiastic pursuit of allegations of abuse of children in institutions. The decision to conduct this inquiry was taken in response to a large number of well argued representations."

Typical among the cases of Operation Rose was that of a Esme Allenby, 54, a care worker whose life was said to be ruined by nine allegations of indecent assault. Though the police never took the claims to trial, she was devastated by the public pursuit of the claims.

A three-year police investigation into sexual and physical abuse at 61 children's homes has been criticised after resulting in only six convictions despite 530 allegations against around 200 care workers. 

Operation Rose was conducted by Northumbria Police, at a cost of £5 million, after a woman in her twenties disclosed to a social worker that she and a friend had been abused as children in care. 

Initial inquiries identified six victims who alleged abuse, dating from the Sixties, by eight suspects at seven homes in four local authority areas. 

Police embarked on a process of "trawling" for information by writing to 1,800 former residents explaining that they were looking into homes where they had once lived. 

As a consequence homes runs by two voluntary agencies and all six local authorities in the force area - Northumberland, Newcastle upon Tyne, North Tyneside, Gateshead, South Tyneside and Sunderland - came under investigation. 

A total of 277 residents and former residents made allegations against 223 care workers for alleged offences including rape, buggery, indecent assault and physical assault. 

Of 32 people who were charged with a total of 142 offences, five were found guilty, one pleaded guilty, 12 were found not guilty, nine had cases withdrawn, four died before their cases were heard and one remained on file. 

Court reporting restrictions, which previously prevented publicity of the Operation Rose trials, were lifted at the conclusion of the final case this week. 

Esme Allenby, 54, of Cramlington, Northumberland, was told she would not face trial for nine counts of indecent assault, dating back 27 years, which she denied. 

The prosecution at Newcastle Crown Court told Judge Maurice Carr that it was in the public interest that the trial did not proceed because vital documents were missing. 

The North-East branch of Falsely Accused Carers and Teachers, an organisation set up after instances of unproved allegations elsewhere in the country, attacked the police approach to gathering complaints. 

Ray Johnston, the co-chairman of Fact (North East), said: "Scores of carers and teachers have had their lives ruined and the lives of their families destroyed by these actions." 

Mr Johnston was suspended from his post as a senior teacher at Netherton Park in Northumberland in August 1997. He said: "I was just fully aware I hadn't done anything to justify being suspended at all and thought it was thoroughly wrong." 

Mr Johnston learnt from colleagues that a girl had accused him of physical assault and eight months after his suspension he was arrested and later charged with five counts of child cruelty and two of physical assaults. 

After years of court adjournments Mr Johnston's case was dismissed after a judge ruled that the three and a half-year delay in the case had breached his human rights. He has now submitted a complaint to the Police Complaints Authority citing victimisation and malicious prosecution. 

A former teacher, Derek Gordon, from Chester-le-Street, Co Durham, said Operation Rose had left him "marked for life" even though he was acquitted of child abuse charges. 

Northumbria Police defended Operation Rose. The assistant chief constable John Scott, said: "It was a thorough and professional investigation. Six people involved in child abuse have been put behind bars as a result of our investigations."