[2] In police work, a mole is an undercover law-enforcement agent who joins an organization in order to collect incriminating evidence about its operations and to eventually charge its members.
A mole may be recruited early in life, and take decades to get a job in government service and reach a position of access to secret information before becoming active as a spy.
[citation needed] For example, James Angleton, director of counterintelligence for the CIA between 1954 and 1975, was reportedly obsessed with suspicions that the top levels of Western governments were riddled with long-term communist agents[1] and accused numerous politicians such as former U.S. Secretary of State Henry Kissinger, former Canadian Prime Ministers Lester Pearson and Pierre Trudeau, former British Prime Minister Harold Wilson and many members of Congress before he was removed in 1975.
In addition, the security clearance process weeds out employees who are openly disgruntled, ideologically disaffected, or otherwise having motives for betraying their country, so people in such positions are likely to reject recruitment as spies.
Therefore, some intelligence services have tried to reverse the above process by first recruiting potential agents and then having them conceal their allegiance and pursue careers in the target government agency in the hope that they can reach positions of access to desired information.