Was That Tear Gas in DC?

Before President Trump walked from the White House to nearby St. John's Church on Monday, authorities cleared protesters from his path. Now a debate is simmering over a simple question: Did they fire tear gas? President Trump and his press secretary insist the answer is no. "They didn’t use tear gas,” Trump told Fox News Radio on Wednesday, per the AP. The US Park Police also says no tear gas was used. Still, people were crying, coughing, and gagging after authorities fired canisters in their vicinity. So what's going on? Semantics might help explain it. The canisters fired may not have technically been labeled "tear gas," but they produced the same effects, reports the Washington Post. The newspaper notes that one canister from the scene was labeled "Skat Shell OC," with the OC standing for "oleoresin capsicum, an oily substance derived from chile peppers."

It's the type of compound broadly termed a riot-control agent in wide use by police departments. The confusion is that many also apply the term "tear gas" to such compounds. When it comes to crowd-dispersal chemicals, "tear gas is anything that makes you cry,” says Dr. Lynn Goldman of the George Washington University Milken Institute School of Public Health. “Pepper spray is a tear gas. But there are all kinds of other ones, too.” The CDC also says such riot-control agents are "sometimes referred to as 'tear gas,'" and the Handbook of Toxicology of Chemical Warfare Agents also uses tear gas as "an informal umbrella term," per the AP. WUSA9, meanwhile, goes further. Its analysis of canisters shows that "not only was natural OC gas used ... but that artificial CS gas, or what is more commonly known as tear gas, was used as well." (More tear gas stories.)