Facebook Inc and Alphabet Inc's Google unit on Tuesday defended their efforts to remove hate speech from social media sites amid questions from lawmakers in an appearance before the U.S. House Judiciary Committee.
Representative Jerrold Nadler, who chairs the panel, said white nationalist groups target communities of color and religious minorities through social media.
"Efforts by media companies to counter this surge have fallen short, and social network platforms continue to be used as ready avenues to spread dangerous white nationalist speech," Nadler said at the hearing.
Social media firms use algorithims and human reviewers to remove hateful speech.
In March, the chair of the House Homeland Security committee wrote top executives of Facebook, Google, Twitter Inc and Microsoft Corp, urging them to do a better job of removing violent political content following the live-streaming of a New Zealand mass shooting.
Neil Potts, a public policy director at Facebook, told lawmakers that Facebook in March "instituted a prohibition on praise, support, and representation of white nationalism and white separatism."
Google wants to be a "part of the solution," company executive Alexandria Walden said at Tuesday's hearing, adding that Google has invested "heavily in machines and people to quickly identify and remove content that violates our policies against incitement to violence and hate speech."
Google's YouTube, which streamed the hearing live, disabled comments on the hearing after numerous hateful and racist postings.
In November, the FBI said U.S. hate crimes jumped 17 per cent in 2017, with a 37 per cent spike in anti-Semitic attacks.
Ellen Hershenov, senior vice president for policy at Anti-Defamation League, told lawmakers the "internet is forcing us to reassess our understanding of how violence may be inspired by such hateful echo chambers."
Representative Doug Collins, the top Republican on the panel, denounced white nationalism. "Free expression, free press and blind justice," he added, are "the very things that foster diversity and deter intellectually bankrupt ideologies like white nationalism."
In response to suggestions social media companies discriminate against conservative viewpoints, Potts said Facebook errs "on the side of allowing more speech."
"We want to give people the voice but we do have to draw a line somewhere," he noted.
Representative Cedric Richmond, a Democrat, said it was important to prevent social media users from preying on weak people to incite violence.
"Just because you are upset with your station in life, and sitting in your momma's basement in your boxers you don't get to spew hate that you know will incite violence because you can hide behind anonymity," Richmond said.