Sentencing is June 25. The investment adviser faces a maximum 59 years in prison and a $4.25 million fine.
Prosecutors say Troxler did business in Dallas from at least 1998 through 2002.
He was convicted of corruptly endeavoring to obstruct and impede administration of IRS laws, four counts of attempting to evade and defeat taxes, and 12 counts of assisting in the preparation and presentation of false and fraudulent tax returns.
