Proud Boys leader Enrique Tarrio pleaded guilty to burning a Black Lives Matter banner in December.
His attorney filed a motion on Saturday to have the judge removed and to reduce Tarrio's sentence.
Tarrio was sentenced to five months in jail in August, and reported to jail on Monday night.
The attorney for Proud Boys leader Enrique Tarrio filed a last-ditch motion on Saturday to reduce his client's five-month sentence for the burning of a Black Lives Matter banner belonging to a historically Black church in the nation's capital.
But WUSA 9 reporter Eric Flack reported on Monday night that Tarrio reported to jail to serve his 155-day sentence anyway.
The incident, which Tarrio pleaded guilty to along with other charges, occurred in December before the January 6 insurrection at the Capitol.
Tarrio's attorney Lucas I. Danise said in the new filing that the sentencing judge in the case, Harold Cushenberry Jr., should be removed due to bias.