A Butler tax preparer investigators accused of helping another person file a false 2015 tax return pleaded guilty to a single federal charge Monday.

Anthony V. Davis, 59, pleaded guilty to aiding or assisting in the preparation or filing of false tax returns before U.S. District Judge Nora B. Fischer. Prosecutors say Davis was caught after an investigation by the Internal Revenue Service.

He faces a maximum of three years in prison, a fine of $250,000 or both, according to federal prosecutors.

Fischer set sentencing for 11 a.m. Dec. 6, according to the U.S. Attorney’s Office in Pittsburgh.