Court records show federal prosecutors handed over a huge cache of evidence — known as discovery — to the defense team this week.
The documents contained more than 190,000 pages of records, including bank and credit-card statements, UTA records, documents from Diehl's accountant and other records, Assistant U.S. Attorney Mark Hirata said.
Hirata also said prosecutors anticipate receiving additional information from four sources, including Jeff Vitek, a onetime Diehl business partner who is cooperating with the government.
Vitek and Diehl were partners in a multimillion-dollar development in 2010 that included securing a $10 million loan from the transit agency that was used to buy land at 12800 South in Draper where UTA planned and built a FrontRunner station. The transaction has been the subject of two scathing Utah legislative audits and is being scrutinized as part of an ongoing federal criminal investigation of UTA.
Diehl was indicted in April, one day after prosecutors announced the government had reached an immunity agreement with UTA in exchange for the agency's cooperation in the criminal investigation. That probe is focused on current and former UTA board members, executives and others involved with the developments around its rail stations.
Diehl, 61, was a UTA board member for more than 10 years, but the indictment focused primarily on his alleged misrepresentations or omissions in bankruptcy documents. Among the accusations was that he failed to report more than $1 million in income from a land deal near the Draper FrontRunner train station.
The seven concealment charges are tied to assets held by Skyline Ventures Associates Inc., a company set up a few months before the bankruptcy filing. Diehl's daughters are listed as the company's owners and managers in state documents, but Diehl really controlled it, according to the indictment.
A review of the seven transactions listed in the indictment by The Salt Lake Tribune found that Diehl took in nearly $600,000 in the 11 months after filing bankruptcy, money he allegedly underreported to the court.
More than $567,000 listed came to Diehl in payments from high-powered Utah real estate developers, a check of the records show, including Utah Speaker of the House Greg Hughes, former House Majority Leader Kevin Garn and Vitek.
Diehl declined to comment on the payments for a story the Tribune published in May.
In a text message sent to The Tribune when the indictment was announced, Diehl proclaimed his innocence.
"I obviously disagree with the government regarding the details involved with my bankruptcy. I look forward to proving my innocence and having my day in court."