Morgan, 49, of the state of Indiana, pleaded guilty to one count of parading, demonstrating, or picketing in a captiol building, the report said on Wednesday.
Morgan has also been ordered to complete 40 hours of community service and pay $500 in restitution, the report said.
Earlier in the day, FBI Director Christopher Wray said a little more than 500 people have been arrested in connection to the attack. He added that hundreds of more investigations and more serious charges are expected.
On January 6, a group of supporters of the former US President Donald Trump entered the US Capitol to protest lawmakers certifying Joe Biden's election victory.