The proofs compiled 30 years ago have shown that Hubbard, who invented a religion followed by celebrities such as Tom Cruise, gave himself a PhD from a sham college he had acquired in California.
The evidence was gathered by secret workers at the British consulate in Los Angeles on behalf of the government, which feared a libel action following its 1968 decision to ban followers from entering Britain to visit the sect's headquarters in East Grinstead, West Sussex.
The dossier, containing the information gathered during the 1970s, included the extraordinary claim by an American official that the sect had sent bogus doctors to hypnotise a legal investigator and declare him 'mentally ill' to thwart his inquiries into their activities.
A signed statement by former senior Scientologist, John McMaster revealed that Hubbard and others faked 'qualifications' in Dianetics, the spiritual 'science' behind Scientology.
"I understand it is asserted that L Ron Hubbard was awarded the degree of Doctor of Philosophy by Sequoia University on February 10, 1953, in recognition of his outstanding work in the fields of Dianetics and Scientology and that the said degree was recorded with the Department of Education of the State of California," the Telegraph quoted him as saying in the statement.
"The position is L Ron Hubbard (and others) acquired premises somewhere in Los Angeles which they had registered as a university called Sequoia and immediately awarded each other doctorates," he added.
The Whitehall officials sent an urgent telegram from London to the British consulate in LA to instigate an enquiry.
The reply on Apr 26, 1977 said, "After exhaustive enquiries we have now tracked down organisation named which was closed down by state authorities in 1971 and all documents impounded. The facts are that it neither has nor ever had approval and its status is not recognised in California ... It is a 'will of the wisp' organisation which has no premises and does not really exist. It has not and never had any authority whatso-ever to issue diplomas or degrees and the dean is sought by the authorities 'for questioning'."
A letter from the California bureau of school approvals about the Sequoia university states, "This institution has never been approved or recognised by this office. Repeated attempts have been made to obtain compliance with the legal requirements. None of these attempts have proved successful."
Sherbourne also said that the Deputy Attorney General looking after the claims, by 'an amazing coincidence' was taken ill and after seeing some 'doctors' was retired 'due to his mental health'.
It is said that the 'doctors' were scientologists who hypnotised him into mental ill-health.