The assassination of Charlie Kirk and its aftermath—including conservatives demanding consequences against those who have criticized Kirk and the brief suspension of comedian Jimmy Kimmel—have fueled a renewed debate over free speech in America. One particular element of that conversation promises to be particularly fraught: calls to punish “hate speech.” After Kirk’s killing, Attorney General Pam Bondi threatened to “target” and “go after” those who engaged in the practice. [time-brightcove not-tgx=”true”]The government, however, generally cannot punish “hate speech” under the First Amendment. There are no “hate speech” laws in America. That makes the U.S. fairly unique. In most other countries, people can be criminally liable for “hate speech,” which is usually defined as statements that disparage racial and religious groups. The U.S.’s unique position on hate speech regulation stems from more than 100 years of history, and the realization that defining this vile speech is difficult, the potential for abuse is great, and such bans may actually harm the very groups they aim to protect. This historical path for the U.S. was far from preordained. In the 1930s, as fascist groups affiliated with the Nazi Party rose up, the U.S. seemed like it could be on its way toward a regime of hate speech laws like the kind that currently exists in Europe. States and municipalities began proposing and passing laws prohibiting speech that incited “group defamation” or “race hatred.” They hoped to prevent the violence that broke out when the fascists assembled and distributed their propaganda. When America entered the Second World War, states and cities moved to enact additional hate speech laws, in part to prevent race riots that threatened to disrupt industrial production and the war effort. But support for these laws was far from universal. Perhaps surprisingly, prominent civil rights groups such as the National Association for the Advancement of Colored People (NAACP) and the American Jewish Committee led the way in opposing hate speech laws. In articles, litigation, and other public forums, leaders of those organizations argued that rather than stifle hate groups, prosecuting hate speakers would draw attention to their ideas and increase the following of these organizations. Read More: Pam Bondi Provokes MAGA Backlash With Threat to Prosecute ‘Hate Speech’Even more significantly, leaders from these organizations—including Louis Marshall of the American Jewish Committee and Thurgood Marshall, the NAACP’s legal counsel in the 1930s and 1940s and a future Supreme Court justice—foresaw how hate speech laws could be turned against civil rights activists. Segregationist officials, for example, could deem opposition to poll taxes, or support of integration, to be a form of “race hatred” against whites. As a result, civil rights leaders insisted that the pursuit of equality depended on freedom for unpopular speech. They argued that the best way to combat hate speech was not through suppression, but by talking back to it, countering bad ideas with good ones. The “true and effective reply to the propaganda of bigots” was not criminal prosecution, but freedom of speech and “a campaign of education” against prejudice, the American Jewish Congress and American Jewish Committee argued in 1938 when they urged New York officials to drop charges against one of most prolific publishers of pro-Nazi material in America. In 1945, the national NAACP advised its local branches to oppose proposed hate speech laws, warning that they “will serve to throttle … any [speaker] which seeks to champion the cause of minority groups.”This opposition contributed to the campaign for such laws beginning to fizzle out in the 1940s. Some of the laws lapsed and were never renewed, some were repealed, and judges struck down others as violations of the First Amendment. Nonetheless, as the civil rights movement gained steam in the 1950s and 1960s, it reinforced the wisdom of the arguments that civil rights groups had made against hate speech laws and forced them to redouble their efforts to fight such prohibitions. Canny Southern officials looked to any legal provision with which they could stifle activists’ advocacy and forestall change. That included branding civil rights advocacy and speech defamatory, a breach of the peace, or hate speech, and hauling activists into courts and jails. In part because of these efforts by Southern segregationists to destroy the civil rights movement, a series of free speech issues reached the Supreme Court in the 1960s. There, the arguments long made by civil rights groups proved persuasive. Led by Chief Justice Earl Warren, the Court effectively did away with the possibility of hate speech laws. The justices issued a string of rulings that instituted strong protections for speakers and enshrined viewpoint-neutrality as the foundation of First Amendment law. In 1963, in Edwards v. South Carolina, the Court invalidated the conviction of Black high school and college students who marched peacefully to protest segregation and were charged with breaching the peace. The Court ruled that the First Amendment did not permit punishment of the “peaceful expression of unpopular views.” The Court rejected the “heckler’s veto,” reaffirming that the government could not silence speakers because of the potentially violent reactions of audiences. A year later, in the seminal New York Times v. Sullivan case, the justices ruled that public officials bringing libel cases must meet the high burden of showing “actual malice” or “reckless disregard of the truth.” Sullivan involved an Alabama police commissioner who sued the New York Times over a truthful publication describing segregationist violence against civil rights protesters. Writing for the Court, Justice William Brennan wrote eloquently of the need to protect the “uninhibited, robust, and wide-open” discourse that was foundational to democracy.Read More: Investigations at Columbia University Clash with Concerns about Free Speech on CampusIn 1969, the Court applied this logic not just to noble speech, like advocacy for civil rights, but also to the very bigotry that activists were fighting to overcome. In Brandenburg v. Ohio, the justices overturned the conviction of a Ku Klux Klan leader who said that “revengeance” might be necessary unless the Supreme Court and other public officials stopped advocating integration and “suppress[ing] the white, Caucasian race.” The Court held that the government could not punish speech unless it was directed to inciting “imminent lawless action” and likely to incite such action. These broad protections for free speech helped empower the civil rights revolution of the 1960s, as well as the other rights movements that emerged in the late 1960s and 1970s. The Court recognized that civil rights activism required controversial and disorderly speech. If libel suits, prosecutions for hate speech, or the “heckler’s veto” could silence activists, the rights movements might have been stifled from the start. Yet, these decisions never settled the debate over hate speech with any finality. In 1977, after neo-Nazis threatened to march in Skokie, Ill., a town populated by Holocaust survivors, it sparked renewed calls for hate speech restrictions. Forty years later, the “Unite the Right” rally of white supremacists in Charlottesville Va., which resulted in a young woman’s death, again fueled calls for bans on hate speech. According to polls, nearly half of Americans, or even more than half, support official restrictions on hate speech. Advocates of hate speech laws argue that society is more endangered by hate speech than by limitations on it, although there is no evidence that hate speech laws have been effective in the U.S. or anywhere else in the world. Yet, history—especially the history of the civil rights movement—suggests that American law’s position on hate speech is wise and principled, although it may be emotionally difficult to accept. Civil rights leaders in the 20th century recognized that the concept of “hate speech” was vague, making laws banning the practice prone to abuse. Laws against hate speech could be used to suppress speech that the government didn’t like. If people couldn’t be sure of what might be deemed “hate speech,” they would have no choice but to self-censor and avoid speaking out. In our time of unrest and violence, we would do well to remember why hate speech laws were rejected — they pose too great a threat to the “robust and wide-open” public discourse that is essential to creating meaningful and peaceful change in a democratic society. The alternative is granting those in positions of power the ability to silence anyone who disagrees with them. Samantha Barbas is professor of law and Aliber Family Chair in Law at the University of Iowa College of Law. She is the author of several books on the history of freedom of speech, including Actual Malice: Civil Rights and Freedom of the Press in New York Times v. Sullivan. Made by History takes readers beyond the headlines with articles written and edited by professional historians. Learn more about Made by History at TIME here. Opinions expressed do not necessarily reflect the views of TIME editors.