Facebook launched a supervisory board to monitor its response to the exploitation of its platform by extremist groups and influence campaigns that have undermined the role of its products as "public squares".
The company, which owns Facebook, Instagram and WhatsApp, said the board would make final decisions about posts that lead to controversy about censorship, misinformation or free speech.
The 20 members of the panel announced on Wednesday come from various countries and include lawyers, human rights activists, journalists and a former Danish prime minister.
Facebook public policy director Brent Harris said the board was the "beginning of a fundamental change in the way some of the most difficult content decisions on Facebook will be made".
Mr Harris said members would operate independently of the Californian company.
Staff would not clarify how many hours the board members would work each week but said they would be compensated at "tech industry standards".
The four co-chairs wrote an editorial setting out their independence credentials.
Helle Thorning-Schmidt was the first female prime minister of Denmark, who led a coalition government from 2011 to 2015 then served as the chief executive of Save the Children International.
Catalina Botero Marino, a Colombian lawyer, was special rapporteur for freedom of expression at the Organisation of American States and dean of the Universidad de los Andes Faculty of Law.
Columbia law professor Jamal Greene is a specialist in constitutional rights adjudication, while Michael McConnell, constitutional law professor at Stanford Law, was US federal circuit judge.
"Board members will serve fixed terms of three years up to a maximum of three terms," the co-chairs wrote.
"They contract directly with the oversight board. We cannot be removed by Facebook.
"Through the founding bylaws of the oversight board, Facebook has committed to carrying out our decisions even though it may at times disagree, unless doing so would violate the law.
"Facebook’s chief executive, Mark Zuckerberg, has also personally committed to this arrangement."
Groups such as the Counter Extremism Project have led exposes of terrorist recruitment material on Facebook and its rivals.
While some material can be removed, the response is far from comprehensive or complete.
Speaking at an online seminar on Wednesday, Alexander Ritzmann, the project's senior adviser, said social media giants had to regain lost credibility to address the concerns of those reporting abuses.
The scrutiny and accountability handed to the regulatory board is only one part of the equation.
"Transparency is the new sustainability. Everybody kind of likes it but nobody knows what it means," Mr Ritzmann said.