House Minority Leader Nancy Pelosi is naming five Democrats to the new House select committee on Benghazi.
The 2012 terror attack on the U.S. embassy in Benghazi, Libya killed four Americans.
Victims included Ambassador Christopher Stevens.
Pelosi was initially skeptical about naming Democrats to the panel.
In a Capitol briefing, Pelosi called the select committee unnecessary. She said House committees have already conducted exhaustive investigations into Benghazi.
Pelosi said two families of Benghazi victims have contacted her to say,"Don't take us down this path again."
Pelosi has previously called the select committee's mission a conspiracy theory in search of a conspiracy.
The five Democrats on the panel are Maryland's Elijah Cummings, California's Linda Sanchez, Washington state's Adam Smith, California's Adam Schiff and Tammy Duckworth from Illinois.
Cummings accused some House Republicans of continuously promoting unsubstantiated and unproven allegations about Benghazi.
He said he agreed to serve on the select committee to "defend the truth."
There will be seven Republicans on the panel, which will be chaired by South Carolina's Trey Gowdy.