The Central London Employment Tribunal has ruled that, although security services and police had colluded with Carillion in covert and illegal blacklisting of construction workers, blacklisted workers who are employed through employment agencies could not be protected by law.

The case of Smith v Carillion heard evidence, revealed for the first time by the Information Commissioner, that a shady organisation called Consulting Association had illegally compiled files, believed to have been supplied by the police and/or security services, on workers, politicians, journalists, lawyers and academics for private companies in the building industry. Dave Smith, a 46 year-old-engineer, had been blacklisted by Carillion and two of its subsidiaries, John Mowlem and Schal International Management Ltd, because of his trade union activities and for raising concerns about safety on building sites, and suffered long periods of unemployment as a result. Despite the companies' admitting they had supplied the malicious information to Mr Smith's blacklist file, the court concluded that legal protection against blacklisting provided under UK employment laws did not extend to agency workers.