Fulton County District Attorney Fani Willis (left) and Donald Trump, right. (Photos: John Disney and Diego M. Radzinschi/ALM) Fulton County District Attorney Fani Willis (left) and Donald Trump, right. (Photos: John Disney and Diego M. Radzinschi/ALM)

When Fulton County District Attorney Fani Willis secured the indictment a year ago Thursday, it was the fourth and most sprawling of the criminal cases against the former president. Trump narrowly lost Georgia to Democrat Joe Biden, and Willis used Georgia's anti-racketeering law to allege that he and 18 others had participated in a wide-ranging scheme to subvert the will of the state's voters.

Willis' team notched some early victories in the case, but explosive allegations raised by one of Trump's co-defendants early this year have caused a delay and could even derail the prosecution.