In
October 1924 the MI5 intercepted a letter
written by Grigory Zinoviev, chairman
of the Comintern in the Soviet Union. In the letter Zinoviev urged
British communists to promote revolution through acts of sedition.
Vernon Kell, head of MI5 and Sir
Basil Thomson head of Special Branch, were convinced that the
letter was genuine.
Kell showed the letter to Ramsay MacDonald,
the Labour Prime Minister. It was agreed
that the letter should be kept secret but someone leaked news of the
letter to the Times and the Daily
Mail.
The letter was published in these newspapers four days before the
1924 General Election and contributed to
the defeat of MacDonald and the Labour Party.
After the election it was claimed that two of MI5's agents, Sidney
Reilly and Arthur Maundy Gregory,
had forged the letter and that Major Joseph Ball, a MI5 leaked it
to the press. In 1927 Ball went to work for the Conservative
Central Office where he pioneered the idea of spin-doctoring.
Research carried out by Gill Bennett in 1999 suggested that there
were several MI5 and MI6 officers attempting the bring down the Labour
Government in 1924, including