Two presidential running mates will answer questions Wednesday night during a town hall on CNN as they look to increase their name recognition and tell voters about the issues that they stand for. While the Green Party presidential candidate, Jill Stein, has only marginal name recognition compared to the other candidates in the race, there will be one other person on that stage who is even less known to the American public: her vice presidential running mate, Ajamu Baraka.

Here’s what you should know about him.

He’s A Civil Rights Activist

Baraka’s biography on his personal website says that he has fought for human rights for four decades, focusing on both domestic and international issues. He’s worked as a grassroots organizer in the Black Liberation Movement and the anti-apartheid movement. Beyond that, he has worked with Central American solidarity struggles, as well.

His biography says that he has been working in the United States to apply the international human rights framework domestically to social justice advocacy for more than a quarter of a century. He has briefed Congress on human rights and has spoken before several United Nations agencies.

He’s Been Tied To Some Controversial Issues

While Stein has been quoted questioning whether or not Wi-Fi in schools hurts children, Baraka has been tied to some more provocative conspiracy theories.

Earlier this year, his work was published in a book that was edited by accused Holocaust denier and 9/11 truther Kevin Barrett, according to the Daily Beast. That book also has some work by Ken O’Keefe — who once explained via YouTube how “Hitler was right” — and Gilad Atzom — who has been accused of anti-Semitism by Palestinian organizers and activists.

For his part, Baraka has disavowed holocaust denial, saying, “ I abhor and reject any individual or group that fails to understand the tremendous suffering of Jewish people during that dark period.”

He said he was unaware of the holocaust denial and that he had merely agreed to include his essay in a book about the theories of “false flags,” or covert operations by unknown or hidden actors to create an incentive to strike back (for instance, 9/11 truthers believe that a state actor like the CIA orchestrated those attacks in order to create a reason for the U.S. to invade the Middle East).

He Has Been Highly Critical of U.S. President Barack Obama, And Many Others

Baraka has referred to Obama as the “Uncle Tom president” and has questioned him on a variety of issues, from what he characterizes as the commander in chief’s “obsequious deference to white power” and his refusal to call the 2015 Charleston church shooter, Dylann Roof, a “terrorist.”

He’s also referred to the celebration of activists and celebrities like Ta-Nehisi Coates, Beyoncé and Bernie Sanders as “media-driven pseudo-opposition” and says “it is increasingly difficult to make the distinction between image and reality, especially when the production of images and symbols is controlled by dominant forces with an interest in keeping us all stupid.”