Former Texas Rep. Ron Paul accused the government of carefully timing an indictment against his former campaign aides in an attempt to harm the reputation of his son, Sen. Rand Paul of Kentucky, who was scheduled to appear the next day on stage in the first Republican primary debate of the 2016 campaign, reports The Associated Press.

Paul testified in a federal courthouse in Des Moines, Iowa, on Wednesday as a witness for the prosecution in a case against two of his former staffers who worked on his 2012 presidential campaign, Jesse Benton and Dimitri Kesari. Prosecutors say the two concealed more than $73,000 in payments made to then-Iowa state Sen. Kent Sorenson in return for his endorsement of Paul in the days leading up to the January 2012 Iowa caucuses.

Paul told the jurors he was suspicious of the timing of the indictment's unsealing, which happened in August, one day before Rand Paul was set to participate in the Republican Party's first debate, according to AP.

"I don't consider that a coincidence," said Ron Paul.

Paul insisted that he didn't know anything about the alleged secret payments, and U.S. Department of Justice prosecutor Richard Pilger portrayed Paul as a victim who was unaware of the plot, according to The Des Moines Register.

"I don't even believe in endorsements - you think I'd want to pay for it?" Paul asked. "I just don't think people are supposed to do that."

He seemed unhappy to have been called to testify against the two, and blamed news organizations and prosecutors for an investigation that morphed into a years-long burden for his family, according to Mother Jones. Paul told the jurors he still stands by Benton, who is married to his granddaughter, also Rand Paul's niece.

"I'm not testifying for the defense," Paul said at one point while Kesari's lawyer was cross-examining him, according to the Register. "I'm testifying for the prosecution. And that's been a heavy burden for my family."

Benton has been charged with one count of making false statements to FBI agents during a 2014 interview, while Kesari faces five charges, including conspiracy and obstruction, according to AP.