GENEVA — The president of the United Nations’ top human rights body has appointed a former New York Supreme Court judge to serve as the third member of a commission investigating possible violations of the rules of war in Gaza.

Gabon Ambassador Baudelaire Ndong Ella, who presides over the UN’s 47-nation Human Rights Council, said Monday Mary McGowan Davis will join William Schabas and Doudou Dienne on the commission created by the council’s July 23 resolution.

Davis, who also was a federal prosecutor and has previous UN experience related to Gaza, will take the place of British-Lebanese lawyer Amal Alamuddin. Alamuddin, who is engaged to marry George Clooney, said she could not accept the role shortly after she had been appointed to it.

A commission report is due in March 2015.

McGowan Davis is likely to prove a controversial choice for Israel, having served on a previous team that investigated a 2008-2009 offensive and whose findings were rejected by the Jewish state.

The UN Human Rights Council ordered the Gaza investigation last month, in the face of fierce opposition from Israel and the United States.

The decision came during a marathon seven-hour emergency session of the 47-nation council, where Israeli and Palestinians delegates accused the other side of war crimes.

The probe team was set up under a resolution lodged by Palestine, which has observer status at the council, but UN officials say its goal is to address all violations of international human rights and humanitarian law in Gaza, regardless of which side is involved.

“In carrying out its work, the Commission of Inquiry will aim to establish the facts and circumstances of human rights violations and crimes perpetrated in order to identify those responsible,” the council said Monday.

Israel has denounced the probe as slanted against it — echoing its criticism of previous UN investigations.

An acting justice on the supreme court of the state of New York from 1986 to 1998, McGowan Davis is a renowned expert on transitional justice and human rights law.

In 2004 and 2005, she worked in Afghanistan’s public defenders’ office, and has also been involved in war crimes justice projects in Sierra Leone, Cambodia and Rwanda.

The Gaza commission is being led by Canadian international lawyer William Schabas, and includes Doudou Diene of Senegal, who has previously served as the UN’s watchdog on racism and on post-conflict Ivory Coast.