The case in which former state Rep. Robin Smith of Hixson is expected to be the star witness for the government is set to go to trial in Federal Court in Nashville on April 22.
Ms. Smith, who resigned and pleaded guilty earlier, is set to testify against former House Speaker Glen Casada and his aide Cade Cothren.
The government expects the trial to last between two and three weeks; the defense expects the trial to last four weeks.
Authorities said in November 2019 that Cothren set up a firm called Phoenix Consulting that was said to be headed by Matthew Phoenix, which in fact was a fictitious name and the actual operator of the firm was Cothren.
The firm was set up to get payments from a program in which legislators could use up to $3,000 each per year for mailings to constituents.
Prosecutors said earlier, "The plea agreement contemplates that Defendant will cooperate with the government in this and related cases. It is anticipated that Defendant will testify in United States v. Casada, et al."
Ms. Smith, who pleaded guilty to wire fraud, at one time headed the state Republican Party.
Her sentencing has been moved back several times and is now set for June 9 at 1 p.m. in Nashville.