The nationwide protests following the death of George Floyd in police custody have put new attention on the U.S. Supreme Court's police and civil rights rulings, and criticisms by one justice in particular that those decisions too often shield law enforcement's misconduct from accountability.

At the Supreme Court, Justice Sonia Sotomayor repeatedly has warned that the court's "one-sided approach" to qualified immunity—more often protecting police—sends an "alarming signal" to law enforcement and the public.

"We have not hesitated to summarily reverse courts for wrongly denying officers the protection of qualified immunity in cases involving the use of force," Sotomayor wrote in a 2017 case. "But we rarely intervene where courts wrongly afford officers the benefit of qualified immunity in these same cases."

A series of petitions at the court now urge the justices to reconsider, restrict or abolish the judge-made doctrine of qualified immunity. The doctrine bars lawsuits against government officials, including state and local police, when they violate someone's constitutional rights, except when their actions violate a "clearly established" constitutional or statutory right.

The justices may announce as soon as June 8 whether they will take up the issue. Their vote, at their private conference Thursday, would come as protests in cities across the country urge greater accountability in instances involving alleged police misconduct.

Sotomayor, a former prosecutor and the only former trial judge now on the Supreme Court, has been the court's most consistent critic of its qualified immunity rulings.

In three recent qualified immunity dissents and one Fourth Amendment dissent, Sotomayor cautioned that the court's decisions were supporting a law enforcement culture that she said views qualified immunity as an "absolute shield" against liability for alleged abuses. And she has cited a 2018 law review article by William Baude of the University of Chicago Law School for data on the court's "one-sided" approach.

"I do think Justice Sotomayor is correct that there is a risk that too strong a qualified immunity doctrine could lead some police officers to believe they are above the law, hopefully not many," said Paul Hughes, a partner at McDermott Will & Emery. "The restrictions imposed by the Fourth Amendment and other constitutional protections may not have the effect of constraining police conduct."

There also is an interrelation between qualified immunity and the extreme examples of police brutality that have dominated the news, Hughes said. That is "a legitimate issue for the court to think through as it considers the doctrine," he said.

Hughes is among the lawyers who have filed petitions urging the justices to abolish the qualified immunity doctrine. More than half a dozen petitions for review have been relisted many times for consideration by the justices in their private conferences in recent weeks, a sign the court is giving the petitions substantial attention. A number have drawn amicus support from cross-ideological organizations.

Sotomayor's criticisms of qualified immunity have sometimes been joined by Justice Ruth Bader Ginsburg. But largely, Sotomayor stands out writing for herself.

In the 2018 case Kisela v. Hughes, the court issued a per curiam summary reversal in favor of a police officer accused of using deadly force. Sotomayor, joined by Ginsburg, said the court's decision "is not just wrong on the law; it also sends an alarming signal to law enforcement officers and the public. It tells officers that they can shoot first and think later, and it tells the public that palpably unreason­able conduct will go unpunished."

A year earlier, in the case Salazar-Limon v. Houston, the justices declined to review a case involving a claim that a police officer used excessive force in shooting a man as he tried to walk away from a confrontation with the officer. Sotomayor, saying the facts were in dispute, would have granted review and reversed. "We have not hesitated to summarily reverse courts for wrongly denying officers the protection of qualified immunity in cases involving the use of force. But we rarely intervene where courts wrongly afford officers the benefit of qualified immunity in these same cases," she said.

In the Supreme Court case Mullenix v. Luna from 2015, the justices reversed the denial of qualified immunity to a police officer who had allegedly ignored a command to "stand by," and shot and killed the driver of a speeding car as it approached speed strips designed to stop or slow it. Sotomayor said the ruling sanctioned "a 'shoot first, think later' approach to policing." The decision, she said, "renders the protections of the Fourth Amendment hollow."

Although not a qualified immunity case, the Supreme Court's 2016 decision in Utah v. Strieff—and Sotomayor's dissent—have gained new attention amid the discussions surrounding the protests of the death of Floyd. The Strieff ruling came amid the early wave of the Black Lives Matter movement.

The Supreme Court majority applied an exception to the exclusionary rule—the attenuation doctrine—which overcame an unconstitutional stop because police discovered a preexisting arrest warrant for a traffic ticket which led to a search and evidence of drugs.

Sotomayor, in a part of her dissent that she described as writing only for herself and drawing on her professional experiences, wrote: "The white defendant in this case shows that anyone's dignity can be violated in this manner. But it is no secret that people of color are disproportionate victims of this type of scrutiny." She continued: "We must not pretend that the countless people who are routinely targeted by police are 'isolated.' They are the canaries in the coal mine whose deaths, civil and literal, warn us that no one can breathe in this atmosphere."

"Until their voices matter too, our justice system will continue to be anything but," Sotomayor wrote.

The pending qualified immunity petitions have been relisted again for the justices's conference on Thursday. No one, except the justices, knows why no decisions have been made yet on whether to grant or deny review in any of them.

Jay Schweikert, a Cato Institute criminal justice policy analyst who works in Cato's qualified immunity project, said, "While it's obviously impossible to know for sure what is motivating the justices' continued delay in these cases, it's reasonable to think the death of George Floyd, and the continuing outrage and chaos his death has provoked, are weighing heavily on their minds."