Millikin will be retiring as soon as a replacement has been found, according to a Reuters report.

He has come under heavy fire for his role in the scandal that has engulfed the automaker this year over its failure to recall millions of vehicles with faulty ignition switches, leading to more than 20 deaths. To help deal with the mess, the company has put together a victim compensation program that will cost it up to $600 million. Additionally, GM is facing an ongoing Justice Department investigation that may produce a big fine and criminal charges against the company. The National Highway Transportation Safety Administration has already fined GM $35 million.

A lot of people can’t believe the lawyer has lasted this long.

“I don’t see how you and [North America General Counsel] Lucy Clark Dougherty still have jobs,” Sen. Claire McCaskill (D-Mo.) said to Millikin during his testimony before congress this summer. McCaskill went on to compare Millikin to former Veterans Administration leader Erik Shinseki, who resigned after the VA hospital scandal earlier this year.

GM (GM) CEO Mary Barra, though, defended Millikin, insisting that he was a key part of her leadership team and that she needed him as the firm continued to fight through the recall scandal, and attempted to get its business back on track.

Apparently, though, she’ll have to do without. One expert told Reuters that its possible Millikin was asked to resign by the company, to shield itself against potential litigation, though a GM spokesperson denied this.

No matter why Millikin is leaving, the search for his replacement will likely get a lot of scrutiny. Will Barra and the board of directors promote from within, or find someone from outside of GM? The latter would be seen as a sign Barra is serious about fundamentally changing the company’s culture, which she and others have blamed for letting the ignition switch defect to go unfixed for years.