Shamgar died Friday at age 94. He will be buried at Har Hamenuchot cemetery in Jerusalem.
"Meir's unique contribution to shaping the legal system is priceless," Netanyahu said. "His firm and consistent belief in freedom of speech, individual liberties and tolerance is reflected in every judgment he made, as is his recognition of the supreme importance of state security."
Netanyahu and Gantz have been working to form a coalition government since their election victories last month. Netanyahu said Monday he couldn't find enough support, and the mandate to put together a working government was given to Gantz.
Shamgar is credited with shaping much of Israel's legal system as the Israeli Defense Force chief attorney and, later, its attorney general and Supreme Court justice and president. He developed the legal framework for Israel to occupy the West Bank, a decision that's been called the "belligerent occupation" by Palestinians. Shamgar, however, also put significant limits on what Israel can do in the West Bank.
He founded the IDF West Bank Court system to handle Palestinian crimes. And Palestinians could appeal court rulings to the Supreme Court even though they weren't officially citizens. He served as Supreme Court chief justice for 12 years, the longest in Israeli history, and extended the court's power to review various government and Knesset decisions.
"President Shamgar is a key figure in Israeli law," Justice Aharon Barak said. "He is a cornerstone of Israel's judicial history. The reality is that the judicial creation is a continuum that in which every just adds a link to the never-ending chain, and Shamgar likely added one of the most important of these links. On foundations laid by his predecessors, he built new and original structures, laying the base for new developments in Israeli law."
Born in 1925 in Danzig, Poland, to Russian-born parents who were members of the Revisionist Party, a young Shamgar belonged to the Beitar youth movement in Nazi-occupied Poland. He fought for the Irgun and was arrested by British forces in 1944. He later studied law by correspondence while in jail and, upon his release, completed his studies in history and philosophy at Hebrew University of Jerusalem.