Born 1963 in Nusaybin, Sancar attended high school in Diyarbakır before going to Ankara University, where he graduated majoring in public law.

[1] Together with fellow scholar Tanıl Bora [de], he translated Jürgen Habermas' first major work "Strukturwandel der Öffentlichkeit" into the Turkish language.

Ahead of the June 2015 general election, Sancar was asked by HDP leader Selahattin Demirtaş, one of his former students, to run for parliament.

In November 2015, Sancar and Erol Dora joined fellow MPs Gülser Yıldırım and Ali Atalan in their hunger strike to protest the ongoing state of exception curfew in the border town of Nusaybin, where since November 13[5] and under the pretext of operating against militant YDG-H members, 70% of the neighborhoods have been cut from electricity, 30% from water supply.

[7][8] According to an interview he gave Sancar was accused of having insulted the President for having declared the Turkish government was in part responsible for the terrorist attack against a HDP rally in Ankara and for having also said to the authorities that a conflict should be prevented in Cizre.