The U.S. Supreme Court has refused to take on a Facebook case that could have set new standards for alleged criminals' access to social media in their defense.

Although prosecutors can dig up evidence from social media to make their cases, companies such as Facebook have quashed criminal defendants' subpoenas under the Stored Communications Act, a move that some defendants have said violates their constitutional rights.

On Monday, the Supreme Court denied certiorari in Facebook v. Superior Court of California. The case questioned whether Facebook's refusal to hand over users' communications violated the Sixth Amendment and due process rights of two men indicted on murder, weapons and gang-related charges.

Gibson, Dunn & Crutcher represented Facebook in its petition for writ of certiorari filed in February. The lawyers challenged a July 2019 order from San Francisco Superior Court Judge Charles Crompton, which held Facebook and Twitter in contempt for refusing to disclose account holders' electronic communications in response to subpoenas from criminal defendants Derrick Hunter and Lee Sullivan.

"The California court's decision erodes the trust in the privacy of electronic communications instilled by the SCA. It prioritizes a criminal defendant's desire to obtain communications from whatever source she prefers—often without the knowledge of the people whose communications are at issue—despite the wishes of social media users who sent the messages and have not consented to sharing them," wrote the Gibson, Dunn & Crutcher attorneys in the petition.

Gibson Dunn's Joshua Lipshutz declined to comment on the case, and Facebook did not respond to a request for comment.

In February, California's First District Court of Appeal directed the trial court to quash the subpoenas, finding that the defendants did not show the requisite finding of good cause for production of the private communications. An order has yet to be handed down to the superior court because Sullivan's counsel at the Law Office of Bicka Barlow and San Francisco attorney Susan Kaplan petitioned the California Supreme Court to review the decision.

In denying Facebook and Twitter's motion to quash the subpoenas, Crompton said Hunter and Sullivan's Sixth Amendment and due process rights were "very important." The judge said, "I think that these rights are important enough in this particular case, as I've said, given the relevance of electronic messages that's been raised in this particular case, with these particular charges and these particular defendants, it would certainly outweigh any … burden [incurred by providers]," according to the Court of Appeal ruling.

Hunter and Sullivan issued the subpoenas in 2014 for the Facebook, Instagram and Twitter accounts of Jaquan Rice Jr., who was killed in a shooting, and state's witness Renesha Lee. Rice allegedly threatened to kill Hunter's 14-year-old brother over a reported gang dispute in person and on Facebook and Instagram, according to the Court of Appeal opinion.

As the case bounced around California's court system, the criminal trial against Hunter and Sullivan moved forward without the subpoenaed information. Sullivan was convicted on all counts, and Hunter was acquitted.

In an April reply brief, Bicka Barlow of the Law Office of Bicka Barlow and Stuart Banner of the University of California, Los Angeles School of Law Supreme Court Clinic urged the court to deny cert. They said the case is a "a terrible vehicle" to address the issue, because the case is moot, has a "bizarre procedural posture" and does not highlight a lower court split, as Facebook alleged in its petition. "If this supposed conflict had ever existed, it would exist no longer, now that the Superior Court's judgment has been vacated by the Court of Appeal," they wrote. "But it never even existed in the first place. In each of the three cases cited by petitioners, the court explicitly avoided reaching the constitutional issues."

A spokesperson for Twitter said that the company will continue to fight to preserve this protection for its users.

"We took a stand against the state court's order in this case because we believe it violates the federal Stored Communications Act and undermines a key purpose of that law—to protect individuals' privacy rights in electronic communications," the spokesperson said.