Justice Sonia Sotomayor seems to have lost respect for her colleagues on the Supreme Court — literally.

In several of her major dissenting opinions last year, Justice Sotomayor dropped the usual decorum, in which justices write that they “respectfully dissent,” and instead flatly declared “I dissent.”

Court observers said it’s a sign of growing frustration on the part of Justice Sotomayor and the high court’s two other Democrat-appointed members, who are limited in their ability to prevail on the big questions of law that are reaching the court with increasing frequency.

The court opens its new term Monday with the justices engaged in brazen public sniping over ethics rules and with nerves still somewhat frayed from the court’s end in June, when the conservative majority issued rulings striking down race-based college affirmative action programs, sided with artists in a dispute over doing business with same-sex couples and erased President Biden’s student loan forgiveness program.

Mike Davis, a court watcher and founder of the Article III Project, said the liberal justices feel embattled.

“I do sense there’s more tension than normal and I think it’s because the three Democratic appointees kind of feel desperate,” Mr. Davis told The Washington Times. “They feel it’s 6-3. Sometimes they can pick off [Justice Brett M.] Kavanaugh and the chief, but they’re going to be in the minority for probably the rest of their lives.”

The tension roiled the court’s final ruling of last term: the student loan case.

Chief Justice John G. Roberts Jr., in the key opinion, delivered a judicial spanking to the three Democrat-appointed justices, who complained that the majority was engaging in judicial adventurism and straining legal reasoning to erase one of the president’s marquee accomplishments. The chief justice called the vehemence of the dissent “disturbing.”

“Reasonable minds may disagree with our analysis — in fact, at least three do,” Chief Justice Roberts wrote, pointing to the dissenters. “We do not mistake this plainly heartfelt disagreement for disparagement. It is important that the public not be misled either. Any such misperception would be harmful to this institution and our country.”

In an appearance at Notre Dame Law School in September, Justice Elena Kagan said the chief justice was wrong to suggest her criticism was out of bounds.

“I don’t think that’s disturbing at all. As I said, I think it would be disturbing if a dissent that thought that the court had gone beyond the proper role of the judiciary, it would be disturbing if you didn’t say that,” Justice Kagan said.

But she did say the public shouldn’t read too much more into the back-and-forth.

“What I do agree with the chief justice on is nobody should take that personally,” she said. “I admire the chief justice enormously. I admire him as a person, I admire him as a judge, I admire him as the institutional leader of the court. There was nothing personal about this and there was no, I think his word was ‘disparagement’ about this.”

Their dispute over executive and congressional power and the role of the courts in refereeing those matters is likely to come roaring back this year.

The second case on the court’s docket this week questions whether Congress can cede its spending powers to an independent executive branch regulatory agency, in this case the Consumer Financial Protection Bureau.

The justices will also hear a case testing how much deference judges should show executive branch agencies in their interpretations of laws written by Congress.

Also on tap for this term are cases involving social media platforms and a major gun rights case.

Off the docket, the justices are involved in an indecorously public dispute over ethics, after news reports have questioned close ties between wealthy conservative figures and Justices Clarence Thomas and Samuel A. Alito Jr.

Justice Kagan has been the most vocal member of the court in calling for a binding code of ethics, while Justice Alito has been vocal about resisting that effort, saying any attempt for outsiders to shackle the court would be unconstitutional.

Whatever the public disputes, it’s conventional wisdom that the justices do get along, and Mr. Davis said that is indeed true.

“Like siblings, Supreme Court justices are stuck together for life. So they try to get along, and they do get along for the most part. It’s a mostly functional family,” he said.

But because so much of the court’s business is done out of sight, yet carries such momentous consequences for the country, the public actions take on more importance.

In the 2000 case of Bush v. Gore, which helped decide the outcome of that year’s presidential election, the late Justice Ruth Bader Ginsburg set tongues wagging when she closed with a flat “I dissent,” rather than the traditional “I respectfully dissent.” Some legal observers labeled it a breach of decorum, while others celebrated her boldness in decrying a tricky ruling.

Justice Sotomayor deployed the stark “I dissent” language in her opinions in the race-based affirmative action case and the student loan case, but her terminology got far less attention than Ginsburg’s in 2000.

The Times reached out to several former Sotomayor clerks, but none agreed to speak for this report.

Vin M. Bonventre, a professor at Albany Law School, said Justice Sotomayor and her two fellow Democratic appointees, Justices Kagan and Ketanji Brown Jackson, are feeling frustrated over the power the GOP-appointed justices wield.

“The liberals on the court are so upset with the fact that they see this conservative Republican supermajority that’s basically running away with constitutional rulings and there’s just nothing the liberals can do about it,” he said. “Of course, the liberals are voting as a bloc too. They’re just as ideologically blind.”

But Mr. Bonventre said what’s going on at the court now is nothing compared to the past, when justices famously feuded with each other and some had no qualms about ripping fellow justices apart in legal opinions.

He said former Justice Sandra Day O’Connor, a GOP appointee, was so repelled by the opinions of the late Justice Antonin Scalia and Justice Thomas that they pushed her further to the left.

“So many times in which Scalia was incredibly nasty to Sandra Day O’Connor as well as [former Justice] Anthony Kennedy, in their opinions talking about their analysis being laughable, being ridiculous, absurd,” Mr. Bonventre said. “This is much much tamer. It’s much tamer than it was even a short time ago when Scalia was on the court.”

• Stephen Dinan can be reached at sdinan@washingtontimes.com.