Enrique Tarrio, leader of Proud Boys, pleaded guilty in December to torching a Black Lives Matter banner.
On Saturday, his attorney filed a motion to remove the judge and reduce Tarrio’s sentence.
Tarrio was sentenced in August to five months imprisonment and reported to prison Monday night.
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On Saturday, Enrique Tarrio's attorney filed a last-ditch motion to reduce his client’s five-month sentence in connection with the burning of a Black Lives Matter banner that belonged to a historically Black church located in the capital.
Eric Flack, WUSA 9's reporter, reported Monday night that Tarrio went to jail anyway to serve his 155-day sentence.
Tarrio pleaded guilty along with other charges to the incident that occurred December before the insurrection at Capitol on January 6.
Lucas I. Danise, Tarrio's lawyer, stated in the new filing, that Harold Cushenberry Jr. should be removed as a sentencing judge because of bias.
At Tarrio's July plea hearing, the judge stated that "my oldest daughter was actually baptized in that church." "She's nearly 40 now, but we attended with some regularity when her was young."
Cushenberry was willing to withdraw, but Tarrio stated, "That's not necessary."
Tarrio, 37, pleaded guilty at the July hearing to one count each of destruction and attempted possession of a large capacity ammunition feeding device.
Tarrio said that the flag-burning occurred during a rally on December 12 supporting former President Donald Trump.
Tarrio, a Cuban American, maintained that the Proud Boys, a hate group that is linked to violence around the US, is not racist, but acknowledged that some of its members have white-supremacist beliefs.
Tarrio's attorney Danise stated in Saturday's filing that Tarrio didn’t know that the BLM flag belonged to the church. Danise claimed that his client was denied due procedure because the government provided "ambiguous evidence" that Tarrio knew the banner belonged at this church.
Danise also claims that Danise's client's sentence was "unreasonably harsh" and "disproportionately when you consider the sentencing goals."