An investigation ordered by Republican Missouri Attorney General Josh Hawley has found that his predecessor's office withheld DNA evidence in a lawsuit over the fatal shooting of a black man by a white St. Louis officer.

Private attorney Hal Goldsmith's investigation released Tuesday found that the office of former Attorney General Chris Koster "was aware of and failed to turn over" DNA evidence taken from Jason Stockley's revolver.

Stockley shot Anthony Lamar Smith after a 2011 chase. Smith's family settled a wrongful death lawsuit in 2013. Stockley, who resigned in 2013, was acquitted of murder in September, setting off weeks of protests.

Koster, a Democrat, ran unsuccessfully for governor last year. He now works for Centene Corp. and didn't immediately respond to a request for comment made through the company.