Retired car dealer James Pfleuger and his son Alan were indicted Wednesday by a federal grand jury for tax fraud.

The senior Pflueger, 84, could face up to 21 years in federal prison if he's convicted. His son Alan, 43, faces a maximum sentence of 14 years in prison, although federal prosecutors said those maximum sentences are unlikely for the two businessmen without criminal records.

The indictment claimed James Pflueger tried to hide assets from the Internal Revenue Service at a time when he was being sued for the Kaloko Dam disaster on Kauai, which killed seven people. James Pflueger faces a manslaughter trial for the Kauai deaths in state court that's still pending.

The indictment charged James Pflueger defrauded the IRS by filing tax returns for three years that did not accurately reflect his income. His federal tax returns reported that he earned $707,871 in 2004 and $4.8 million in 2007. The indictment claimed he “received income in addition to the total income reported,” but it did detail how much more money Pflueger made those years.

His son Charles Alan Pflueger, who is called Alan, now owns the family Honda auto dealership at the corner of Bishop and Beretania Streets downtown. The indictment charged him with filing three years worth of false tax returns.

The indictment charged the younger Pflueger received "substantial income in addition to" the $695,724 reflected on his IRS returns for 2005, $241,114 for the year 2004 and $198,213 in 2003. But federal prosecutors did not detail how much more money the younger Pflueger received.

Alan’s attorney David Scheper spoke to KITV 4 News from Los Angeles, and said his client will be vindicated.

"We are of course deeply disturbed and disappointed by the IRS' decision to prosecute this case as a criminal case, rather than resolving this as they should have through the audit process," Scheper said.

The indictment also claimed James Pflueger set up a trust in the Cook Islands -- located in the South Pacific -- to hide money from the sale of property in California in 2007.

"Proceeds from that sale of the California property went to the trust account which was located in Switzerland. Mr. Pflueger is also charged with not disclosing the existence of that account to the federal government," said Clare Connors, an assistant U.S. attorney in Honolulu who is prosecuting the case.