PORTLAND, Maine, Nov. 22 -- The office of the U.S. Attorney for the District of Maine issued the following news release on Nov. 21, 2024: A Windham man pleaded guilty Wednesday in U.S. District Court in Portland to conspiring to tamper with Clean Air Act monitoring devices and obstructing an agency proceeding. According to court records, between January 2017 and September 2020, Isaac Allen, 34, the owner of Red Barn Diesel Performance, conspired with a local truck sales business to download so more PR