A leading business figure dubbed by a trade union 'the Prince of Darkness' for cutting thousands of jobs is to oversee the government's £1bn court reform programme.

The government today announced that Tim Parker, chair of the Post Office, Samsonite and the National Trust, has been appointed chair of the board of HM Courts & Tribunals Service. He will take up his post on 27 April following the retirement of Robert Ayling, chair since HMCTS was established in 2011.

HMCTS said today that Parker, who has 'spent time as an economist' in the Treasury and has been chief executive of shoe retailer Clarks, car repair company Kwik-Fit and motoring association AA, 'will bring a wealth of knowledge and experience in business transformation'.

Justice secretary David Gauke said: 'Tim's expertise will be vital as we deliver our reform and modernisation of the courts and tribunals system - making it more convenient, easier to use and providing better value for the taxpayer.'

Parker was dubbed 'the Prince of Darkness' by the GMB union after allegedly turning up in his Porsche to sack a group of factory workers and halving the 7,000 workforce at the AA. He is reputed to be worth £200m, but has hit out at high boardroom pay and called for income tax on the wealthy to be increased. A decade ago he was, briefly, first deputy mayor of London under Boris Johnson.

Parker said today: 'I am delighted to be joining HMCTS and look forward to spearheading its programme of reform - bringing courts and tribunals into the digital age and ensuring they are providing the best service possible for the public.'

Lord Burnett, the lord chief justice, and Sir Ernest Ryder, senior president of the tribunals, said Parker was taking up the reins 'at a critical time'.