A serial sex offender who raped two 15-year-old girls after police failed to link his DNA to earlier offences was jailed for life yesterday.

Victims’ groups and women’s rights campaigners criticised the police blunders that allowed Mark Campbell, once dubbed the “Thursday rapist”, to evade justice for four years after he was first arrested.

During that time Campbell, 38, from Chichester, West Sussex, raped the teenagers and carried out several other sex attacks, as well as two burglaries.

Sussex police took a DNA sample from Campbell in October 2002, after he was arrested in a woman’s garden on suspicion of being a “peeping Tom”. However, the samples were not sent away for analysis until September 2006, when Campbell’s swabs were found to match those taken from some of his victims.

The father-of-two sobbed yesterday as he was convicted of a six-year campaign of offences against women in Sussex. Judge William Wood, QC, told Campbell that he would serve at least ten years in prison.

“It is difficult to exaggerate the degree of harm done,” the judge said, adding that many of the victims would be “looking over their shoulders for the rest of their lives”.

Campbell first struck in February 1998, when he assaulted a 27-year-old woman in her home while her three young children slept upstairs. A year later he falsely imprisoned a 12-year-old girl and indecently assaulted a 15-year-old.

In May 2000 he raped a 21-year-old woman, after which police began a manhunt.

Officers carried out a mass DNA screening of local men, but Campbell did not fall into their target group — partly because his home was half a mile outside the area where detectives believed that the rapist was living.

When he was finally tested his sample was placed in a freezer but was never sent away for analysis.

Two years later, in August 2004, he raped two 15-year-old girls in the back of his van. A month before that, he had sexually assaulted a 16-year-old girl while her younger sister slept in the same double bed.

In September 2006 a cold case review discovered the untested DNA and it was analysed.

Jeremy Paine, assistant chief constable of Sussex Police, said that there were “no excuses” for the four-year delay in catching Campbell. “It should not have happened and we are very sorry that it did,” he said.

“We have done everything we can to learn the lessons so that nothing like it can happen again.”

A police spokesman said that changes to the law surrounding DNA samples, as well as new procedures, would prevent the error being repeated. He said that one senior officer and one member of police staff, whom he refused to name, had received formal words of advice.

Women’s campaigners condemned the police response as inadequate. Ruth Hall, of Women Against Rape, called for those responsible to be sacked. “Not just the one officer who didn’t send off the sample, but those who are responsible for closing the inquiry down . . . and not ensuring that there were regular checks made, and an open mind kept. They left women defenceless against this man.

“We have had inquiry after inquiry, law change after law change, and nothing ever happens, because until these people are held accountable, nobody takes it seriously.”

Maggie Ellis, director of Chichester’s Life Centre, which offers counselling and support to victims of sexual violence, described the DNA oversight as “a human error with disastrous consequences”.

Campbell was found guilty of 13 offences between 1998 and 2004, and acquitted of one count of indecent assault and one count of sexual assault. Police believe he may have struck several more times, beginning as early as 1995.

Assaults and errors

February 1998 Campbell assaults mother of three in her home

September 1999 Falsely imprisons 12-year-old girl

May 2000 Rapes for the first time. Police formally link a series of offences and begin Operation Bobcat

June 2002 Operation Bobcat wound down

October 2002 Campbell arrested as a suspected peeping Tom and gives DNA sample to police

July 2004 Assaults 16-year-old girl in her bed

August 2004 Rapes two 15-year-old friends

September 2006 Ten untested DNA samples, including Campbell’s, discovered in police freezer and sent for analysis

October 2006 DNA results come back. Campbell is arrested

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