Democrats, as the minority party in Congress, do not have the power to set the legislative agenda, but they can hold informal events to highlight their proposals and criticize Republicans, Reuters reported.
"We will examine ongoing threats to free and fair elections,” House Democratic Leader Hakeem Jeffries said in a statement announcing the forum. He said it also will look into Trump's pardons of more than 1,500 people who were criminally charged with participating in the January 6 violence.
The Trump administration has sought states' voter registration lists, leading to fears the information could be misused. Trump has urged states to abandon mail-in ballots and has hinted at running for a third presidential term in 2028, which would violate the US Constitution.
The January 6, 2021 riot, a failed attempt by thousands of Trump supporters to overturn Trump's 2020 defeat by Democrat Joe Biden, sent lawmakers running for their lives and injured about 140 law enforcement officers.
Four people died during the chaos, including a Trump supporter who was shot dead by police. One police officer, who was attacked by protesters, died the following day. Four other police officers subsequently died by suicide.
Trump insisted the election was stolen from him through fraud, even though he lost a series of court cases challenging the election result.
Some Republicans blamed far-left activists for the attack, and party lawmakers set up a new committee last year to "uncover the full truth" from that day.
“True accountability requires focusing on facts, not selective storytelling for partisan gain," the chairman of the subcommittee, Barry Loudermilk, said in reference to the Democrats' hearing.
Also on Tuesday, Enrique Tarrio, a former leader of the Proud Boys far-right militant group who was found guilty of helping to plan the riot, has announced a "patriotic and peaceful march" to honor the memory of protesters who died that day. He received a 22-year sentence for seditious conspiracy but was subsequently pardoned by Trump.