[3] Notable documentaries Garbus has made are The Farm: Angola, USA, Ghosts of Abu Ghraib, Bobby Fischer Against the World, Love, Marilyn, What Happened, Miss Simone?, and Becoming Cousteau.

[6][7] In 1992, Garbus graduated magna cum laude with a bachelor's degree in history and semiotics from Brown University.

[9] In 1998, she co-founded an independent documentary production company, Moxie Firecracker Films, with fellow Brown University alumna Rory Kennedy.

In 2005, Garbus collaborated with partner Rory Kennedy to executive-produce Street Fight about the 2002 Newark mayoral election; it was nominated for an Academy Award.

[10] In 2007, Garbus' film Ghosts of Abu Ghraib premiered at Sundance and won an Emmy for Outstanding Non-Fiction Special of 2007.

[13] Garbus' 2012 film, Love, Marilyn featured Elizabeth Banks, Ellen Burstyn, Glenn Close, Viola Davis, Jennifer Ehle, Lindsay Lohan, Lili Taylor, Uma Thurman, Marisa Tomei, Evan Rachel Wood and others reading from Monroe’s never-before-seen private writings.

In January 2018, The New York Times announced that Garbus and a documentary crew had been "basically living in the...newsroom since Inauguration Day [with] full access to the Russia investigation and much more.

[17] In May 2018, HBO premiered Garbus' documentary, A Dangerous Son, which portrays three families as they deal with severe mental illness of three different children, and their efforts to get treatment and navigate the health care system.

[18][19] In September 2020, Garbus released All In: The Fight for Democracy, a documentary film about voting rights in the United States starring voting rights activist Stacey Abrams and featuring other American politicians including former United States Attorney General Eric Holder and then-Representative Marcia Fudge.