Adam Liptak

A Supreme Court argument about whether North Carolina may bar registered sex offenders from using Facebook, Twitter and similar services turned into a discussion of how thoroughly social media have transformed American civic discourse.

The justices’ remarks, which indicated easy familiarity with the major social media services, suggested that they would strike down the North Carolina law under the First Amendment. Justice Elena Kagan said that President Trump, every governor and every member of Congress has a Twitter account. “So this has become a crucially important channel of political communication,” she said. “And a person couldn’t go onto those sites and find out what these members of our government are thinking or saying or doing.”

Justice Anthony M. Kennedy said that social media sites had become, and in some ways had surpassed, the public square as a place for discussion and debate. “The sites that Justice Kagan has described and their utility and the extent of their coverage are greater than the communication you could have ever had, even in the paradigm of public square,” Justice Kennedy said.

The North Carolina law has economic consequences, too, Justice Sonia Sotomayor said. “Take something like LinkedIn, which many, many people in our society today are looking for jobs there, but high school students are permitted to look for jobs and to post their personal data on that site,” she said.

Alarmed by Donald Trump’s record of filing lawsuits to punish and silence his critics, a committee of media lawyers at the American Bar Association commissioned a report on Trump’s litigation history. The report concluded that Trump was a “libel bully” who had filed many meritless suits attacking his opponents and had never won in court. But the bar association refused to publish the report, citing “the risk of the ABA being sued by Mr. Trump.” David J. Bodney, a former chairman of the media-law committee, said he was baffled by the bar association’s interference in the committee’s journal.

“It is more than a little ironic,” he said, “that a publication dedicated to the exploration of First Amendment issues is subjected to censorship when it seeks to publish an article about threats to free speech.” In internal communications, the bar association’s leadership, including its general counsel’s office and public relations staff, did not appear to dispute the report’s conclusions. But James Dimos, the association’s deputy executive director, objected to the term “libel bully” and other sharp language in the report, saying in an Oct. 19 email that the changes were needed to address “the legitimately held views of ABA staff who are charged with managing the reputational and financial risk to the association.”

In a decision with far-reaching implications for the television industry, the Supreme Court ruled that Aereo, a start-up streaming service, had violated copyright laws by capturing broadcast signals on miniature antennas and delivering them to subscribers for a fee.

The 6-3 decision was a victory for the major television networks, which had argued that Aereo’s business model amounted to a theft of their programming. The judges’ ruling leaves the current broadcast model intact while imperiling Aereo’s viability as a business after just over two years in existence.

In arguments before the court in April, the broadcasters contended that Aereo and similar services threatened to cut into a vital revenue stream -- the billions of dollars they receive from cable and satellite companies in retransmission fees, the money paid to networks and local stations for the right to retransmit their programming. The networks said this revenue was so essential that they would have considered removing their signals from the airwaves had the court ruled for Aereo.

The start-up contended that the service it provided through warehouses of small antennas was merely helping its subscribers do what they could lawfully do since the era of rabbit-ears: watch free broadcast television delivered over public airwaves. Both Barry Diller, who heads Aereo owner IAC/InterActiveCorp, and Aereo CEO Chet Kanojia have expressed doubt about whether Aereo could remain in business if the Supreme Court ruled against it.

The Supreme Court has turned down an appeal from James Risen, a reporter for The New York Times facing jail for refusing to identify a confidential source.

The court’s one-line order gave no reasons but effectively sided with the government in a confrontation between what prosecutors said was an imperative to secure evidence in a national security prosecution and what journalists said was an intolerable infringement of press freedom.

The United States Court of Appeals for the Fourth Circuit, in Richmond (VA), ordered Risen to comply with the subpoena. Risen has said he will refuse. “I will continue to fight,” Risen said.

His lawyer, Joel Kurtzberg, urged the Justice Department to hold its fire. “The ball is now in the government’s court,” Kurtzberg wrote. “The government can choose not to pursue Mr. Risen’s testimony if it wants to. We can only hope now that the government will not seek to have him held in contempt for doing nothing more than reporting the news and keeping his promises” to his sources.

The Supreme Court seemed to have conflicting impulses in considering a request from television broadcasters to shut down Aereo, an Internet start-up that the broadcasters say threatens the economic viability of their businesses.

On the one hand, most of the Justices seemed to think that the service was too clever by half. “Your technological model,” Chief Justice John Roberts Jr told Aereo’s lawyer, “is based solely on circumventing legal prohibitions that you don’t want to comply with.”

But Justice Stephen Breyer, echoing sentiments of other members of the court, said “what disturbs me on the other side is, I don’t understand what a decision” against Aereo “should mean for other technologies,” notably cloud computing.

The Justices seemed keenly aware that their ruling would have vast implications for the broadcast industry and for technical innovations involving cloud computing.

Justice John Paul Stevens, who turned 94 recently, is a mild man with an even temperament. He has a reverence for the Supreme Court, on which he served for almost 35 years until his retirement in 2010, and he is fond of his former colleagues.

But there was a hint of anger in some of his remarks when I went to see him last week in his Supreme Court chambers. He said the court had made a disastrous wrong turn in its recent string of campaign finance rulings.

“The voter is less important than the man who provides money to the candidate,” he said. “It’s really wrong.”

He talked about what he called a telling flaw in the opening sentence of last month’s big campaign finance ruling. He filled in some new details about the behind-the-scenes maneuvering that led to the Citizens United decision. And he called for a constitutional amendment to address what he said was the grave threat to American democracy caused by the torrent of money in politics.