A man who created an illegal database of information on construction workers has been fined the maximum £5,000 and ordered to pay £1,187 costs at Knutsford Crown Court.

Ian Kerr held details on 3,213 construction workers and traded their personal details for profit through his company TCA. The court heard last week that construction firms paid TCA £478,937 between April 2006 and February 2009.

The operation ran from the 1970s until privacy watchdog the Information Commissioner's Office (ICO) seized the data from TCA’s premises on 2 March 2009.

The ICO will take enforcement action this week on the 17 construction firms that paid Kerr for details on workers, subject to any representations made by the companies.

The firms are not subject to fines but can be named by the ICO. New powers for the watchdog due next year will allow firms in such cases to be fined.

“Ian Kerr colluded with construction firms for many years flouting the Data Protection Act and ignoring people’s privacy rights," said deputy information commissioner David Smith.

"Trading people’s personal details in this way is unlawful and we are determined to stamp out this type of activity. Kerr’s covert operation denied people their information rights under the Data Protection Act. "

The ICO has received more than 1,827 enquiries from members of the public and as a result more than 120 individuals who appeared on the database have now had their information returned to them.