Conservative who tilted the balance on US supreme court

Antonin Scalia, who has died aged 79, was the man who had the decisive fifth vote out of nine judges that guaranteed conservative dominance of the US supreme court for the past 30 years.

He made possible a whole string of decisions, not least that in the Citizens United case in 2010, which opened the gates to a flood of money in American politics, or Bush v Gore, the 2000 Florida election case which brought George W Bush into the White House.

The appointment of his successor, which under the constitution lies with the president, and of that successor’s confirmation, which belongs to the Senate, will have an unpredictable but determining influence on the politics of the next decade.

Scalia made no bones about his political conservatism. He was, for example, a passionate opponent of abortion. He upheld the death penalty and opposed restraints on gun ownership: he was himself a hunter of deer and big game.

He dissented from attempts to free prisoners from the Guantánamo prison camp. He dissented, too, in Lawrence v Texas (2003), the case in which the court struck down laws against sodomy. As for Bush v Gore, he said to his critics simply: "Get over it."

He was not, however, an altogether predictable or automatic conservative. Possessed, as even his enemies conceded, of an exceptionally powerful legal intellect and an unusual gift for writing his opinions lucidly and often with wit, he reached his own conclusions on the basis of his own strong principles.

He was not, for example, as some American conservatives are, a simple racist. In a 1989 case, City of Richmond v JA Croson Co, he said: "We are just one race here. It is American." However, he did muse publicly about whether black students might not do better if they did not go to elite universities. Mistrusted judges In his own way he was a radical, a judge who mistrusted judges and who therefore wanted to reduce their ability to impose their own opinions on the constitution.

He wanted to reverse the whole trend of American jurisprudence over the past century, in which it had come to be accepted that law must have a policy, and that the duty of a judge was to do what was right for society.

Scalia believed that a judge must simply declare what the law was. He must return to the original meaning of constitutional texts, and to the natural meaning of legal texts. In one specific, he was quite successful. It used to be the case that liberal judges would rely heavily on the “legislative history” of a case, examining how a particular law came into being.

Since Scalia began to attack this practice, it has diminished dramatically. He was not only influential to the point of dominance on the supreme court. His two great innovative emphases, on “originalism” and “textualism”, that is, on looking to the original intentions of the framers of the constitution in 1791 and on interpreting statutes in their plain meaning, which 30 years ago were seen as reactionary and eccentric, have become increasingly influential on the bench and especially in the great American law schools, once the undisputed home of liberal doctrine. Immigrant background Scalia was born in Trenton, New Jersey to Salvatore and Catherine (née Panaro), but the family soon moved to New York. His father was an immigrant from Sicily who ended up as a professor of Romance languages at Brooklyn College, and his mother was a first-generation Italian-American who worked as an elementary school teacher.

He was educated at the Jesuit Xavier high school in Lower Manhattan, where his academic brilliance was recognised early. He went on to the Jesuit university, Georgetown, in Washington, and then to Harvard Law School. He spent his second year at Fribourg University in Switzerland and also stayed for some time in Britain.

After six years with a Cleveland law firm, in 1967 he went to teach law at the University of Virginia and later at the University of Chicago, where he was active in the beginnings of the Federalist Society , a movement of conservative lawyers.

In 1972 he took a position in the Nixon administration in Washington, and in 1974 he was brought into the president’s powerful Office of Legal Counsel.

In 1982 he was appointed by President Ronald Reagan to the court of appeals for the District of Columbia and in 1986 to the supreme court.

Scalia – Nino to his friends – was an unusually divisive figure on the bench. His partisans and even some of his opponents enjoyed his cutting wit. Most liberals, however, saw him as caustic and arrogant. For a generation he was, his supporters and his detractors agreed, almost a “one-man court”. Evenly split between four liberals and four conservatives, the court will now struggle to decide important cases on abortion, immigration, voting rights and affirmative action.

Scalia's legal and political positions were underpinned by a strong, traditionalist Catholic faith. He preferred Tridentine Latin ritual and once told a startled interviewer from the New Yorker that of course he believed in the devil.

In 1960 he married Maureen McCarthy. She survives him, along with their five sons and four daughters.