But Mr Joe Barton, a Republican from Texas, told Mr Dorsey: "We wouldn't be having this discussion if there wasn't a general agreement that your company had discriminated against conservatives".
Sandburg said, "In the first 3 months of 2018 alone, over 85 percent of the violent content we took down or added warning labels to was identified by our technology before it was reported". Sandberg also added that Facebook employs 20,000 security and safety personnel who work 24 hours a day.
This will be the first time Sandberg has publicly faced significant questioning about Facebook's role in the 2016 election. And Facebook's CEO, Mark Zuckerberg, ran the gauntlet of the House and Senate in April, following the revelations of the Cambridge Analytica data harvesting operation.
"The committee takes this issue very seriously, and we appreciate that Facebook and Twitter are represented here this morning with an equivalent and appropriate measure of seriousness", Senator Burr of North Carolina said.
A spokesperson for Twitter declined to comment, but in past hearings Twitter officials have affirmed the gravity of the situation.
Sheryl Sandberg, chief operating officer of Facebook Inc., speaks during a news conference at Station F, a mega-campus for startups located inside a former freight railway depot, in Paris, Jan. 17, 2017.
Earlier this year the company said it was taking aggressive measures to combat inauthentic accounts.
Dorsey addressed the topic when several members of the US House of Representatives brought up a tweet with a picture threatening late Arizona Senator's John McCain daughter, Meghan, which took hours to be removed from the site.
"What we know is we must commit to a rigorous and independently vetted set of metrics to measure the health of public conversation on Twitter", Mr Dorsey said.
Laura Rosenberger, the Director of the Alliance for Securing Democracy at the German Marshall Fund, told ABC News that likely won't be a problem for the Senate Intelligence Committee, as that committee in particular has been "steeped in understanding the challenges posed by foreign interference".
Trump "routinely tweets false statements created to mislead Americans and foster discord", said Rep.