Three days after her birth, her father resigned as chief counsel of the Senate Rackets Committee to run his brother's campaign for presidency.

[3][4] She appeared at age 3 in the 1963 Robert Drew documentary Crisis: Behind a Presidential Commitment saying hello to U.S. Justice Department official Nicholas Katzenbach by phone from the office of her father, who was U.S. Attorney General at the time.

[8] Kennedy's life has been devoted to equal justice, to the promotion and protection of basic rights, and to the preservation of the rule of law.

She started the RFK Training Institute in Florence, Italy, which offers courses of study to leading human rights defenders across the globe.

Nominated by President George W. Bush and confirmed by the U.S. Senate, she is on the board of directors of the United States Institute of Peace,[11] as well as Human Rights First, and Inter Press Service in Rome, Italy.

She is a patron of the Bloody Sunday Trust (Northern Ireland) and serves on the Editorial Board of Advisors of the Buffalo Human Rights Law Review.

[9] Lawyers for Ecuadorean plaintiffs in the long-running lawsuit against Chevron Corporation for environmental and human health damages at the Lago Agrio oil field hired Kennedy to conduct public relations for their cause.

[15] Kennedy has criticized the treatment of New York teenager Kalief Browder during his extended time in pretrial detention at Rikers Island.

[17] In 2016, Kennedy campaigned for adoption of S 5998-A/A 8296-A, referred to as "Kalief's Law," in the [New York State Legislature], which would have guaranteed speedy trials to defendants being held in pretrial detention.

[27] Less than a week after his release from Rikers Island, Bronx District Attorney Darcel D. Clark announced she would no longer pursue a case against Hernandez.

On June 21, 2018, in response to President Donald Trump's decision to enact a 'zero-tolerance' policy of family separation on immigrants entering the United States illegally, Kennedy joined organizations including the Dolores Huerta Foundation, the Texas Civil Rights Project and La Union Del Pueblo Entero to launch the 'Break Bread Not Families Immigration Fast and Prayer Chain.

[29][30] The campaign, which raised funds to support the reunification of immigrant families, argued Trump administration policy was "not only immoral, it is also illegal under U.S. and international law.

"[31] On June 23, 2018, the Break Bread Not Families campaign held a prayer vigil in the American border town of McAllen, Texas.

Participants included former United States Secretary of Housing and Urban Development Julian Castro, United States Senator Ed Markey, Congresswomen Rosa DeLauro, Barbara Lee and Annie McLane Kuster, Congressman Joseph P. Kennedy III, and actors such as Aisha Tyler,[33] Alfre Woodard, Julia Roberts,[34] Lena Dunham, and Evan Rachel Wood.

[36] Kennedy was threatened with arrest by U.S. Customs and Border Protection agents after repeatedly attempting to speak with officials inside Ursula about the use of chain-link cages to house children separated from their families.

A police report said Kennedy had trouble speaking, was swaying and told an officer that she may have accidentally taken a sleeping pill earlier that day.

In a court appearance on July 17, 2012, Kennedy said local hospital tests found no traces of drugs and that her doctor believed she had suffered a seizure.