WASHINGTON, D.C. — Prosecutors in the case against Doug Jensen, one of the first among a crowd of rioters to breach the U.S. Capitol on Jan. 6, 2021, painted the Des Moines man as laser-focused on one goal: Disrupting the peaceful transfer of power from then-President Donald Trump to President-elect Joe Biden. 

"Mr. Jensen got what he came for," said Assistant U.S. Attorney Emily Allen, who gave the prosecution's opening statement Tuesday in Jensen's trail. She was referring to the hours that the delay caused in Congress' ceremonial certification of Biden's election victory. 

The defense did not attempt to claim Jensen was not present at the Capitol on Jan. 6, but painted a distinction between the Capitol rioters "dressed in costume" and those "dressed for battle." Jensen, the defense argued, was the former. 

"This is not a 'whodunnit' case," defense attorney Christopher Davis said in his opening remarks, referencing the many pictures and videos that show Jensen inside the Capitol that day.

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The opening statements followed two full days of jury selection. Jensen faces seven criminal charges, including a felony count of civil disorder, which carries a maximum sentence upon conviction of five years in prison.

The videos and images of Jensen at the Capitol on Jan. 6, 2021, are at the heart of the prosecution's case. As part of its opening statement, it showed video of Jensen entering the building, arguing with U.S. Capitol police officers and pursuing Officer Eugene Goodman up a stairway. 

Other images show the Iowa native confronting an officer with arms spread wide and emerging seemingly unfazed from haze caused by a cracked-open fire extinguisher. 

Allen emphasized that Jensen was one of the first 10 rioters to breach the Capitol. After being escorted out once, he waited at a broken window for another opportunity to slip back in, she said. Jensen did not leave the Capitol until being escorted out a second time, Allen said.

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The prosecution said it plans to call seven witnesses, including Goodman, who is seen on video guiding Jensen, at the lead of a cadre of rioters, away from the Senate chamber, where lawmakers were still evacuating. FBI Special Agent Tyler Johnson, who conducted an interview with Jensen in Des Moines days after the attack, and a U.S. Secret Service agent tasked with evacuating Vice President Mike Pence from the Capitol,  also will testify. 

Davis, Jensen's attorney, directed the jury's attention to Jensen's Jan. 6 apparel, a beanie and black shirt with a large "Q" on it, in homage to QAnon. The conspiracy theory asserts that a "deep state" apparatus run by political elites, business leaders and a child sex ring that includes Hollywood celebrities worked against Trump. Davis said Jensen "believed (QAnon) 100%."

Before the riot, Trump and his allies spread the false narrative that Vice President Mike Pence somehow could have overturned the results of the 2020 election. Davis told jurors they will hear Jensen implore police officers to “do their job” and arrest Pence, who was presiding over the Senate on Jan. 6.

“He believed they were obligated to do it,” Davis said. “He believed that martial law was going to be instituted.”

Davis urged the jury to separate Jensen's individual actions from the full scope of the riot, arguing that Jensen did not "lay a hand on" or harm anyone. 

"Judge his actions and what he did," Davis said. "Separate it from that day and judge him." 

The jury is comprised of 10 men and four women, including two alternates. 

The trial is not expected to last longer than a few days, the judge said. 

Jensen is the first of eight Iowans charged with taking part in the incursion at the Capitol to go to trial. Three have pleaded guilty, and one, Daryl Johnson of St. Ansgar, was sentenced to 30 days in jail.

More than 870 people have been charged with federal crimes for their conduct on Jan. 6. About 400 of them have pleaded guilty. Juries have convicted eight Capitol riot defendants after trials. None of the defendants who had jury trials was acquitted of any charges.

More on the lead-up to Jensen's trial:

The Associated Press contributed to this article.