(WASHINGTON) -- The Supreme Court on Tuesday overturned the conviction of an online stalker from Colorado, tightening the standard by which threats made on social media can be punished as crimes.
Justice Elena Kagan, writing for a 7-2 majority, said the "the First Amendment still requires proof that the defendant had some subjective understanding of the threatening nature of his statements."
In 2016, Colorado prosecuted the plaintiff, Billy Raymond Counterman, winning a state court conviction by showing that hundreds of Facebook messages Counterman sent to a female singer-songwriter were objectively threatening and received that way by the victim.
He served 4½ years behind bars, even though he has always maintained that he never intended to threaten the musician, Coles Whalen.
"The state must show that the defendant consciously disregarded a substantial risk that his communications would be viewed as threatening violence," Kagan wrote.
That the state did not prove evidence of intent or state of mind "is a violation of the First Amendment," she wrote.
Whalen has not yet publicly commented on the decision. Her younger sister, Marita, previously told ABC News that some of Counterman's messages "had a significant impact on [Whalen] -- that lightheartedness that she used to always carry, sharing that joy with other people, it really got dampened. She became much more protective and afraid."
Justices Amy Coney Barrett and Clarence Thomas dissented.
"Counterman communicated true threats, which, everyone agrees, lie outside the bounces of the First Amendment protection," Barrett wrote. "He knew what the words meant. Those threats caused the victim to fear for her life, and they upended her daily existence. Nonetheless, the court concludes that Counterman can prevail on a First Amendment defense. Nothing in the Constitution compels that result."
Legal scholars supportive of Counterman's case say the decision bolsters free speech protections and reduces the chance of "criminalizing misunderstandings" -- as Counterman's attorneys put it in previous court documents.
Critics of the ruling, however, warn it will make it more difficult for law enforcement to protect people online at a time when threatening behavior is rampant.
"Stalkers are often oblivious to reality, and if you require the state to have to show that they understood that their words were threatening and creating this fear of physical violence, you could actually let a lot of stalkers go," Colorado Attorney General Phil Weiser said in an interview with ABC News earlier this year.
Kagan acknowledged those concerns on behalf of the court's majority, but wrote in her opinion on Tuesday that the new standard would not sacrifice "too many of the benefits of enforcing laws against true threats."
"The rule we adopt today is neither the most speech-protective nor the most sensitive to the dangers of true threats," she wrote. The balance keeps "much of what is important on both sides of the scale."