Peter Lawrence spearheaded a high-profile campaign to establish what happened to the University of York chef, who was aged 35 when she was last seen in March 2009 near her home in Heworth in York.
However, a family statement released today by Mr Lawrence’s close friend, Martin Dales, confirmed that he had died aged 74 in St Leonard’s Hospice in York on Thursday last week.
The statement said: “He will be sorely missed by his family and friends who request privacy at this sad time and there will be no further comments from the family.
“It is sad that nearly 12 years after Claudia’s disappearance from York Peter never found out what has happened to her.
“He was a very private person thrust into the full glare of the media and despite a tireless campaign to find her, he also selflessly devoted himself to helping others with missing relatives through the charity, Missing People.”
The statement also paid tribute to his work in creating the new Guardianship (Missing Persons) Act, known as Claudia’s Law, to assist people in dealing with the financial and business affairs of a missing person.
Despite North Yorkshire Police launching its biggest ever investigation, no-one has ever been charged in connection with Miss Lawrence’s disappearance.
A month after she vanished, the case was escalated to a murder investigation, but police confirmed in 2017 that the inquiry was being scaled back, although it would not be closed.