A Lakewood man was sentenced Wednesday to 21 months in federal prison for preparing false tax returns. Hieu Mattison, 53, was sentenced in federal court in Denver, according to the acting U.S. attorney for Colorado. Mattison, owner and primary tax return preparer of AAAE Financial in Lakewood, filed 34 false tax returns for 16 individuals for the tax years 2008 through 2012 for a total tax loss of $133,544.