[2][3] Nisar was born in 1954 in Lahore, West Punjab, into a Punjabi Muslim Arain family.

[4] Nisar was educated at the Cathedral High School no 1 in Lahore where he matriculated and enrolled at Government College University (GCU) where he graduated with a B.A.

[12] In 2000, Nisar was among those judges at the Lahore High Court, who when given chance to either resign or accept military provisional constitutional order enacted by Military Dictator General Musharraf, took the oath under the new provisional constitutional order and was continue to allow hearing cases at the Lahore High Court.

[16] Upon hearing these developments, Chief Justice Chaudhry suspended the appointment order and marked such actions as "unconstitutional", using his constitutional powers granted by the Judicial Commission.

[18] He was a member of the Supreme Court bench which heard the case against 21st Constitutional Amendment, the amendment which authorized the establishment of military courts to hear terrorism cases after the incident which killed 141 people including 132 children in a school in Peshawar on 16 December 2014.

Nisar has been criticized by some notable academics, journalists, and politicians for his judicial activism and over-involvement in the day-to-day affairs of the government.

[23][24] Despite Election Commission of Pakistan ordering to provide security to all candidates contesting in General Elections 2018, he ordered removal of security[25] from all non-government but high profile politicians, most of who had been part of the previous governments which included PML(N) and JUI politicians.

Their claim was further strengthened when a leader of ANP, Mr Bilour was killed by suicide bomber on 10 July 2018 in Peshawar during election campaign.