A federal tax fraud conspiracy trial began Monday for two Brunswick men who claimed the Internal Revenue Service had no authority to tax people’s incomes. One of the men, F. William Messier, 70, is accused of failing to pay taxes on hundreds of thousands of dollars he made leasing the use of radio towers on his property and obstructing the government’s attempts to recover the money. The other man, 78-year-old David Robinson, with whom Messier co-authored a book about the IRS, is accused of helping Messier avoid paying taxes. Messier’s attorney, Michael Minns, admitted Monday at the start of the trial in U.S.