It isn’t clear why Mr Crowther has left his post at the pub chain.
The new CEO has 20 years’ experience in pubs and brewing, as well as holding senior positions at supermarket chain Sainsbury’s.
Of his appointment, Mr Lawson said: “It’s a great pleasure to be returning to the pub sector and I am hugely excited to join the Liberation Group… I am looking forward to meeting the people, our customers and to fully immersing myself in the company.”

Pictured: Mark Crowther has left his post as CEO after 11 years at the company. (Liberation Group)
Commenting on the change of management, Richard Grainger, Executive Chairman of the Liberation Group, said: “Mark Crowther has contributed significantly to the success of the business and I want to extend the thanks of the board and staff to him.
“Jonathan Lawson’s wide-ranging executive experience across the leisure sector will enable him to drive the business onward and fulfil the Board’s expectations for the Group. We very much look forward to welcoming him into the business.”