The Criminal Cases Review Commission (CCRC) has faced intense scrutiny over the body’s handling of the Andrew Malkinson and Oliver Campbell cases, two of the most serious miscarriages of justice in UK legal history.

Karen Kneller, who had led the organisation since 2013, announced her departure on Thursday morning. Her resignation follows a warning by the House of Commons justice committee in May that her position had become untenable.

Mr Malkinson spent 17 years in prison for a rape he did not commit. His appeals were rejected twice by the CCRC, and his eventual exoneration came only after his legal team conducted their own DNA testing, which dismantled the case against him.

A subsequent review concluded that Mr Malkinson might have been released a decade earlier had the CCRC pursued new DNA evidence available as early as 2009. In the aftermath, thousands of other cases are now under review.

MPs criticised Ms Kneller’s evidence to the justice committee regarding the commission’s failures, describing it as “unpersuasive” and urging her resignation.

The former CCRC chairwoman, Helen Pitcher, resigned in January, alleging she had been made a scapegoat over the Malkinson case. She has since been succeeded by Dame Vera Baird, the former victims’ commissioner, who is currently overseeing a review of the organisation.

Dame Vera said: “The CCRC has a vital role to play in the criminal justice system, but confidence in the organisation has been badly damaged. Confidence in our work must be restored. I thank Karen for her work at the CCRC over many years.”

Amanda Pearce, who is the CCRC’s casework operations director, has been appointed as interim chief executive.