Charles Fried, a legal scholar and ethicist who explored questions of morality and law but also engaged in self-examination of his own views, including backing constitutional abortion rights decades after he argued against them as solicitor general during the Reagan era, died Jan. 23 at 88.

The death was announced by Harvard University, where Dr. Fried began teaching law in 1961. No other details were immediately made public.

In legal and academic circles, Dr. Fried became a powerful voice as a gradualist who favored court decisions that built upon, rather than upended, existing laws and systems — despite once urging the Supreme Court to strike down Roe v. Wade, the 1973 ruling on the constitutional right to abortion.

In the political world, he was part the conservative GOP establishment that stood against former president Donald Trump and, at times, aligned himself with Democrats. In December, he wrote a defense of Claudine Gay, then the Harvard president, who resigned in January amid allegations of plagiarism and fallout from her testimony to Congress about how to confront reports of antisemitism on campus linked to the war in Gaza.

“If I were a university president pressed to answer yes or no whether the student speech in question would subject the students to discipline,” Dr. Fried wrote in the Harvard Crimson, “I would have to reply that, yes, it depends on the context.”

For more than a half century, Dr. Fried’s lectures and books peered into many corners of the law and legal theory — from probing the philosophical groundings of attorney-client relationship to making the case that any type of government-sanctioned torture is amoral and illegal.

Yet his deepest influence came from work that sought to stress-test constitutional principles and the Supreme Court’s role in interpreting them.

Dr. Fried became one of leading proponents of an idea known as “constitutional doctrine” that, in its broadest view, represents a code of legal ethics and standards that would leave little room for politics in deciding cases. He increasingly raised alarms over “legal realism,” the concept that the courts must take into consideration prevailing social interests and public policy.

“The ambition of the law goes further: each legal decision should be referable to a rule or principle,” he wrote in his book “Saying What the Law Is: The Constitution in the Supreme Court” (2004), “it should be justifiable not just by the good that it does but as part of the fabric of the law.”

His views took on added resonance because of his time in the crosscurrents between politics and the Supreme Court, serving in the Reagan administration from 1985 to 1989 as solicitor general. Selecting Dr. Fried raised many eyebrows in Washington. Despite his credentials as a professor and author, Dr. Fried had not tried a case in court in 24 years before he assumed one of the highest positions in the Justice Department. (He was previously deputy solicitor general.)

“Oral arguments are still the hardest part of my job to get used to … I feel nervous every time I argue before the Supreme Court,” he told The Washington Post in 1985, six months into the job.

He argued more than 20 cases before the high court as solicitor general, including losing a 1986 case in which the Supreme Court, on a 5-4 vote, upheld a court-ordered plan that required half of state trooper promotions in Alabama go to Black officers. (Dr. Fried argued for the government that the promotions should be less than 50 percent Black and reflect the state’s racial demographics.)

In 1989, he unsuccessfully argued for the reversal of Roe in the case Webster v. Reproductive Health Services over a Missouri antiabortion statute. He was no longer solicitor general, but the Justice Department asked him to lead the case because his replacement was not yet appointed.

In a November 2021 essay in the New York Times — about seven months before the Supreme Court overturned Roe — Dr. Fried appealed to save the landmark ruling. He said the decision was bigger than abortion and provided the framework for legal battles such as expanding LGBTQ+ rights.

“I made these points in good conscience, drawing on a mix of history, precedent and what I saw as the interests of the rule of law,” he wrote of his earlier attempt to strike down Roe.

“To overturn Roe now would be an act of constitutional vandalism — not conservative, but reactionary,” he added.

The comments were part of his political evolution, which played out in speeches, interviews and op-ed pages. Dr. Fried took on a self-appointed role as a conscience of conservatives dismayed by the growing right-wing grip on the Republican Party.

Dr. Fried was active in the 2008 presidential campaign of Sen. John McCain (R-Ariz.) but then publicly broke ranks and announced that he planned to vote for Barack Obama. Dr. Fried thought McCain’s choice of Alaska Gov. Sarah Palin as his running mate was too dangerous “at a time of deep national crisis.”

During a Senate Judiciary Committee hearing in 2011 on the Affordable Care Act, often called Obamacare, Dr. Fried was asked by Sen. Dick Durbin (D-Ill.) for his opinion on critics’ claims that demanding citizens to have insurance is equivalent to forcing them eat vegetables.

“That would be a violation of the 5th and the 14th Amendment, to force you to eat something,” Dr. Fried replied. “But to force you to pay for something? I don’t see why not. It may not be a good idea, but I don’t see why it’s unconstitutional.”

Dr. Fried made public endorsements for Hillary Clinton in 2016 and Joe Biden in 2020. Trevor Potter, president the Campaign Legal Center, a nonprofit group where Dr. Fried served on the board, said Dr. Fried’s experience as a young boy fleeing antisemitism in Europe in the late 1930s gave him a deep affinity for “the rule of law.”

“He saw what happened when a settled system is radically overturned,” said Potter. “This informed his views all his life.”

Charles Anthony Fried was born April 15, 1935, in Prague. His father was a factory owner and industrialist, and his mother was a homemaker. The family fled in 1939 with Nazi forces occupying parts of Czechoslovakia and antisemitism on the rise. They arrived in the United States in 1941 after spending nearly two years in Britain. The family settled in New York.

“I am a refugee,” Dr. Fried said in a 2023 Harvard Law forum, referring to the European Jewish diaspora from World War II.

He graduated from Princeton University in 1956 with a degree in modern languages and literature, and then studied jurisprudence at the University of Oxford, getting a bachelor’s degree in 1958 and master’s degree in 1960. He returned to New York and received a law degree from Columbia Law School later in 1960, and went on to clerk for Supreme Court Justice John Marshall Harlan II.

After Ronald Reagan’s election as president in 1980, Dr. Fried served in advisory roles in the administration and was a special assistant to the attorney general from 1984 to 1985. A decade later, in September 1995, he began a nearly four-year term as associate justice of the Supreme Judicial Court of Massachusetts while teaching constitutional law at Harvard Law School.

Outside of government, he argued several major cases before the Supreme Court, notably Daubert v. Merrell Dow Pharmaceuticals in 1993 in a case alleging birth defects linked to an anti-nausea medication, Bendectin. The case, in which Dr. Fried was hired to represent Merrell Dow, established standards for the use of expert and scientific evidence in federal courts.

Among his more than 10 books were treatises on how moral and political philosophy can be applied to contemporary law, including “An Anatomy of Values” (1970) and “Right and Wrong” (1978). In his 1991 book, “Order & Law: Arguing the Reagan Revolution,” Dr. Fried discussed his goals and struggles as solicitor general and his appearances before the Supreme Court.

Survivors include his wife of 65 years, Anne Summerscale, and two children, Gregory and Antonia.

Dr. Fried liked to share insider tips from his appearances before the Supreme Court. Few questions often meant the justices had likely already made up their minds, he said. Being grilled was always a better sign.

“It’s not a professor with nine students,” he recalled in a 2013 interview. “It’s nine professors with one student.”