Born November 10, 1919, in Carnegie, Pennsylvania, to Italian emigrant parents, Aldisert attended the local public schools.

He volunteered and joined the United States Marine Corps, serving as battery commander in the Pacific Theater (1942 to 1946), attaining the rank of Major.

He then finished his legal studies using the GI Bill, and received his Juris Doctor in 1947 from the University of Pittsburgh School of Law.

[2] President Lyndon B. Johnson nominated Aldisert to a seat on the United States Court of Appeals for the Third Circuit vacated by Judge Austin Leander Staley.

In addition to sitting on many appellate panels after taking senior status, Judge Aldisert also traveled to England, Germany, Italy, the former Czechoslovakia, and to Poland in 1980 (when that nation began to rebel against communist rule) to lecture on American legal principles.

[6] Judge Aldisert dissented in an ABSCAM sting case, in which a Philadelphia jury had convicted city councilmen of corruption, claiming that the FBI tactics resembled those in totalitarian Nazi Germany or Italy.

The United States Supreme Court ultimately vindicated Judge Aldisert's dissenting view which found the measures constitutional; Chief Justice John Roberts wrote the unanimous opinion in Rumsfeld v. Forum for Academic & Institutional Rights, Inc.[9] In 2005, Judge Aldisert became the first recipient of the "Distinguished Appellate Jurist Award", bestowed by the American Bar Association's Council of Appellate Lawyers.