AN ENVIRONMENTAL activist has taken legal action after finding his name is on a secret blacklist used by companies to vet new workers.

Former civil engineer Mike Hamblett discovered 18 months ago he was among 3,213 people on the list, used by 44 businesses.

He was contacted by lawyers acting for about 150 people involved in ongoing legal action in the High Court.

They are petitioning top judges to obtain a copy of a secret court order which allegedly lets firms access information about blacklisted workers.

The blacklist mainly involves construction workers but also environmental and animal activists.

About eight people in Oxfordshire are believed to have been on the blacklist.

Mr Hamblett believes his name may be on the list because he was jailed for two weeks in 1993 following an arrest at a protest against the extension to the M3 at Twyford Down, Hampshire.

The Osney resident, 60, was also fined in 2009 after a council tree worker was pushed over and injured his backside on a chainsaw which had been switched off.

In 2007 he was taken into custody for stopping contractors painting new parking lines in his street.

Mr Hamblett said: “It’s a terrible shock to find people in secret have been discussing your life without you knowing anything.

“It’s very sinister. We need to sue these people to make sure it doesn’t happen again.”

He is calling on the Government to take action to insist “that every person on the list should be contacted”.

The GMB union believes about a third of the people on the blacklist are currently aware their names are on it.

This week GMB, which along with unions Unite and UCATT is assisting claimants, petitioned the High Court.

They are trying to obtain a copy of a secret order acquired by eight blacklisting companies last October that allegedly allows them access to information about blacklisted workers.

In 2009 Mr Hamblett appealed against his convictions for battery and hindering the use of a chainsaw and related equipment but was not successful. He was fined £215 and ordered to pay £300 costs.