A number of Clark's theories have been dismissed by police or have been subsequently disproven. Some links suggested in Clark's books were also previously investigated and discounted by police before the books were published.
The New Millennium Serial Killer In
The New Millennium Serial Killer, Clark claimed that Halliwell was responsible for the 2002 murder of Rachel Wilson in
Middlesbrough. However, in November 2021 Keith Hall was jailed for the murder after pleading guilty, and Clark was forced to admit that Halliwell had not committed the attack. Clark and his investigative partner Tim Hicks had previously been reprimanded by
Cleveland Police for claiming in the
North Yorks Enquirer and in the
Daily Star that Halliwell, and not this man, was responsible, with the latter article being ordered to be removed as it was prejudicial to the inquiry (the suspect was still under investigation at the time). Clark had previously claimed that Wilson's murder was one of three similar killings committed in the area by Halliwell alongside
Donna Keogh in 1998 and Vicky Glass in 2000. After the individual was convicted of Wilson's murder in 2021 he claimed that Halliwell was still responsible for the other two murders. In the same month as the conviction in the Wilson case three unrelated individuals were charged with the
murder of Caroline Glachan, another case Clark had claimed was committed by Halliwell. Police have firmly ruled out any connection between Halliwell and the murder of
Melanie Hall, another case Clark claimed to have been committed by Halliwell, and in 2019 detectives had already announced they had DNA evidence in the case. Detectives are also already known to have DNA evidence in two other cases Clark alleged were linked to Halliwell: the "
Bath Rapist" case and the murder of
Lindsay Rimer.
North Yorkshire Police also insist that there is no evidence linking Halliwell to the
disappearance of Claudia Lawrence, with
Wiltshire Police pointing out that they have
CCTV evidence of Halliwell in
Swindon on the night she disappeared in
York (over 200 miles driving distance away). They also pointed out that Halliwell would have no reason to be in Yorkshire, with his only relative in the area (some distance away in
Huddersfield) having died several years before the disappearance. In 2018 highly regarded
miscarriage of justice organisation
Inside Justice investigated the Razzell case as part of a
BBC documentary,
Conviction, but in fact concluded that the conviction was safe and concluded there was no evidence linking Halliwell to the crime other than rumour.
Yorkshire Ripper: The Secret Murders A number of murders Clark and Tate claimed could be linked to Sutcliffe in their book
Yorkshire Ripper: The Secret Murders already have DNA evidence, such as the murders of
Barbara Mayo,
Eve Stratford,
Lynne Weedon and
Lynda Farrow, and investigators are known to already have a copy of Sutcliffe's DNA and have been able to rule him out of unsolved cases as a result, such as in the
Lesley Molseed case. Barbara Mayo was already ruled out as a Peter Sutcliffe victim by police in 1997, and the DNA sample in her murder case has not been linked by police to that of Weedon, Stratford or Farrow, showing the murders were committed by different people. The Home Office confirmed that it was, indicating that Sutcliffe can be ruled out of unsolved murder cases in which there is existing DNA evidence such as in the Mayo, Stratford, Weedon and Farrow cases. He then repeated this claim in 2017, but police subsequently revealed to him that Sinclair was imprisoned during both of the murders on firearms charges and confirmed this in a
Freedom of Information request, meaning Sinclair could not have been responsible for the Templeton Woods killings and completely disproving Clark's claim. Clark was forced to admit this in his 2021 book on Sinclair. He subsequently claimed that Sinclair's brother-in-law could have been responsible instead. In 2007 a local man, Vincent Simpson, had been tried for one of the murders after a 1 in 40 million DNA match was found between his DNA and samples found on the victim's clothing, but he was found not guilty by a majority verdict at the conclusion of the trial. ==List of titles==