“The growing movement of peaceful mass demonstrations by Negroes is something new in the South, something understandable ... Let Congress heed their rising voices, for they will be heard.” (New York Times editorial, Mar. 19, 1960)

On Tuesday, March 29, 1960, 10 days after the New York Times ran the editorial supporting the rights of blacks in the South to protest, it published a full-page ad titled “Heed Their Rising Voices.” The ad, created by four Southern clergy, fulminated against police departments and government officials throughout the South—in Georgia, Alabama, Florida, South Carolina, North Carolina and Virginia—for terrorizing peaceful protesters in the South who were standing up to segregation. The ad was sanctioned by four Southern clergy and dozens of Hollywood heavyweights. The group intended to lay bare the abuses of what it called the “Constitution Violators.”

“Heed Their Rising Voices” also detailed harassment that Dr. Martin Luther. King, Jr. had endured: Authorities “have bombed his home almost killing his wife and child. They have assaulted his person. They have arrested him seven times for ‘speeding, ‘loitering,’ and similar ‘offenses.’” It petitioned for funds to support a legal defense for King, who had been indicted for perjury by the State of Alabama. (The State claimed King had lied on his 1956 and 1958 tax forms.)

Here’s the full text of the ad:

The ad listed dozens of names in support, including celebrities (Nat King Cole, Marlon Brando, Sammy Davis, Jr., Mahalia Jackson, Shelley Winters), activists (John Lewis), and several clergy.

While Lester Bruce (L.B.) Sullivan, the public safety commissioner in Montgomery, Al., was not named in “Heed Their Rising Voices” he claimed he was offended by its content. When the Times refused to retract the ad Sullivan filed a defamation suit against the paper, claiming his reputation had been harmed by factual errors in the advertisement. Under Alabama state law, Sullivan could claim defamation without having to prove he had been harmed, and the New York Times could not use truth as part of its defense because there was at least one erroneous error in the advertisement: King had only been arrested four times, not seven.

The Alabama court ruled in favor of Sullivan, granting him $500,000 in damages.

“Libel laws were the province of the states and provided very little protection for reporters,” says Ken Paulson, President of the First Amendment Center of the Newseum Institute and Dean of the College of Media and Entertainment at Middle Tennessee State University.

The New York Times appealed, and the Supreme Court took the case. On March 9, 1964, four years after the original ad had run, the Court ruled unanimously in favor of the Times. The Court found that the State of Alabama did not “sufficiently protect freedom of speech and freedom of the press as required by the First and Fourteenth Amendments.”

Justice William Brennan, Jr., wrote the majority opinion. “We hold today that the Constitution delimits a state’s power to award damages for libel in actions brought by public officials against critics of their official conduct.” The opinion was revised to include not only public officials, but all public figures.

Sullivan had claimed that the factual errors in the New York Times advertorial had defamed him. But the Court felt otherwise. Brennan wrote that errors were “inevitable” and the Court differentiated between factual misstatement and intent to harm.

This was a new standard for libel. The actual malice standard required public figures (and officials) to prove that the reporter intended to print or broadcast false information about them, or published information with “reckless disregard for the truth.”

The case was a landmark decision for the press, giving greater muscle to free press and free speech than anything that had come before. “In First Amendment circles, Times v Sullivan is widely considered the most important decision the Supreme Court rendered in the modern 20th Century,” wrote Roy Gutterman in an article for Forbes in 2014. Gutterman is director of the Tully Center for Free Speech at Syracuse University and an associate professor of communications law and journalism. “Times v Sullivan has had an impact on just about every free speech and free press case for the past half century, influencing everything from how we accept debate and tolerate speech we disagree with to our legal definitions of privacy, obscenity and indecency. The case has been integral to forging rules for access to public meetings, public places and commercial speech as well as the free speech rights of just about anyone you care to list -- journalists, confidential sources, lawyers, campaign donors, pornographers, comedians, religious zealots and hate-mongers.”

The ruling had such influence that many credit the “actual malice” standard with the wave of investigative reporters that followed in its wake. It launched a new era of in-depth reporting, from which journalists emerge such as Woodward and Bernstein, who gained notoriety for breaking the Watergate scandal.

“Sullivan freed up news organizations to pursue the stories that needed pursuing,” Paulson said. “It allows you to write stories about the local [businesspeople] who don’t want you questioning their ethics and stories about the mayor who doesn’t want you to ask about a relative of his who is on the payroll. The large media companies always had high-paid attorneys, but Times v. Sullivan gave weeklies and small newspapers the confidence to report things they might otherwise not have.”

The Court considered the long battle for civil rights that had been fought to that point, and the implication the ruling would have for the future. Sullivan v. Times was taken “against the background of a profound national commitment to the principle that debate on public issues should be uninhibited, robust, and wide-open, and that it may well include vehement, caustic, and sometimes unpleasantly sharp attacks on government and public officials.”

Actual malice is tough to pin down because it is difficult to prove what someone intended. But the Supreme Court ruling does not give carte blanche to reporters. Journalists can and do lose defamation lawsuits. But it is much harder to lose a case in the United States then, say, the United Kingdom, which has far more restrictive libel laws than here.

Many cases that yield important Supreme Court rulings are the product of activists seeking to change America through the courts. In Sullivan v. New York Times, it was a case that ended up there almost by accident—and it wasn’t even an article that was at its heart. It was a newspaper advertisement. Yet perhaps no case has had such an enormous impact on journalism.