In recent years, many political movements—including the prodemocracy protests in Hong Kong, Yellow Vests demonstrations in France, and Black Lives Matter movement in the United States—have unfolded against a hazy backdrop of police-fired tear gas.
Around the world, law enforcement officers rely on tear gas to disperse crowds, but its use is controversial. Proponents say it is a crucial tool for maintaining public order, while some experts argue there are better ways to respond to protests.
How dangerous is tear gas?
Military services and law enforcement agencies worldwide classify tear gas, a colloquial term for a range of chemical compounds used in riot control, as a nonlethal weapon. However, exposure can cause blindness, chemical burns, respiratory failure, and even death. It has also been linked to miscarriages [PDF]. Additionally, canisters have struck and killed people when fired at close range.
Are there any regulations on its use?
Using tear gas in warfare is prohibited under multiple international agreements, including the 1992 Chemical Weapons Convention.
Domestic use remains largely unregulated despite international guidelines [PDF]. Most countries do not publicly share how often authorities use tear gas. Police across the United Kingdom and 72 percent of U.S. departments, however, are required to report use of chemical irritants. There is no legal obligation in any country to record the number of deaths or injuries attributed to tear gas, and little public data exists on how much tear gas countries ship or store.
There are also almost no restrictions on international sales of tear gas, though some countries, including the UK and United States, require manufacturers to get export licenses to sell their products abroad. This is meant to prevent supplies from reaching repressive security forces. Even so, gaps in the law—and, sometimes, knowing government approval—have allowed UK and U.S. companies to export tear gas to regimes that violate human rights.
How have police in different countries used tear gas?
Tear gas was historically used in military conflict and by colonial powers suppressing local uprisings. Today, most countries use it to disperse crowds.
According to U.S. policing documents, tear gas and other nonlethal weapons help officers gain control of a situation without using deadly force. The aim is to apply escalating force until a crowd disperses to prevent a “major riot situation,” though some studies suggest that this approach amplifies tensions instead.
Use of tear gas is widespread in both democracies and nondemocracies. In Hong Kong, authorities fired more than ten thousand canisters over six months in 2019. In the United States, police have fired tear gas at Black Lives Matter protesters in at least one hundred cities since May 2020. Authoritarian governments, such as in Bahrain and Iran, routinely deploy tear gas against peaceful protesters.
Still, some countries use it less frequently than others. In Iceland, half a century passed between documented tear gas deployments, despite a series of large environmental protests in the 2000s. In Sweden, police were forbidden from using tear gas for crowd control until 2012.
Why the gap? Experts say it comes down to different approaches to crowd control and political protests. “Riot control agents are much more frequently used to suppress communication rights than they are used to stop actual riots,” Anna Feigenbaum, author of a seminal book on tear gas, told Vice. Tear gassing, experts argue, is often a method of deterring dissent, used as a first response rather than a last resort.
What are the alternatives?
Some critics say tear gas should be banned from use in law enforcement. Several Democrats in the U.S. House of Representatives have proposed a bill to do just that.
Other experts say the problem lies in a policing paradigm that defaults to the use of force. Even where tear gas is less prevalent, police use repressive tactics to shut down protests, they say. Police use tear gas comparatively infrequently in Britain, for instance, though British forces and police deployed it extensively in Northern Ireland. But, like in other countries, they still prevent assembly by constructing barriers and using kettling, a controversial tactic of cordoning crowds.
There are other approaches. In Stockholm, for example, officers known as dialogue police negotiate with protesters and explain police actions. In Berlin, police use signs and announcements to keep protesters apprised of their intentions. Spain’s police use third-party negotiators [PDF], who mediate information exchange between the police and public. Proponents say such community policing practices, which seek to facilitate peaceful political expression rather than repress it, can avoid the escalation that often ends in police use of tear gas.