It seems like tear gas is being used quite offensively, rather than defensively, which is not surprising in that that is what happens most of the time there are protests in the United States. The use of tear gas and impact munitions as offensive weapons goes against the guidelines set out in the UN Basic Principles of Force. It also challenges the exception in the Chemical Weapons Convention for riot control agents as this exception was based on these agents being used for defensive purposes. Law enforcement are supposed to be able to use these tools defensively if people, either themselves or others, are under threat. 

This kind of offensive, very weapon-like, very violent use of tear gas that we’re seeing — often against peaceful protesters, or certainly against protesters that don’t pose any threat to the life of officers — would not fall under those basic provisions.

From the footage, the street clearing for Trump to have his Bible photo looks like a clear violation of the purpose of these riot control weapons. You saw there completely peaceful protesters on a street in broad daylight, where there was no need to be dispersing them through a toxic weapon. 

And this was rapid, it was intense. A lot of canisters were fired in a very short period of time, which is quite dangerous. The canisters were being shot — what looked like from the footage — directly at people, or at least not a far distance in front of them, which is protocol — to fire the tear gas at the ground a good distance in front of protesters so there’s room to disperse and escape.

Like many of these things around law enforcement, there are no direct laws that are easy to point to and be like, “Oh, this officer violated this use of crowd control.” 

The two major international things that we have are, one, the UN Basic Principles of Force. Those are guiding principles, they’re not law. The idea is that the police should not be using anything at all unless there is a threat against them, and then they should start with the least injurious, the least lethal form (which is usually deemed to be tear gas) and then work their way up — so rubber bullets would be after tear gas and then, much later, would be live ammunition. The UN Basic Principles of Force are what any localized police protocol or law enforcement protocol is supposed to be following.

The other thing is the Chemical Weapons Convention, which is the international treaty that permits the use of tear gas for law enforcement purposes. They do that by differentiating tear gas from other forms of chemical weapons by calling them “riot control agents” and creating a special class of chemical weapons — basically, lighter chemical weapons — that are then allowed. That’s why journalists say, “Outlawed in war, but allowed in peace.”

Tear gas is dangerous in three major ways. First, it is a kind of poison that gets into your lungs. It’s regulated by dosage, in the same way that you could think of something like Ibuprofen being regulated by dosage. Too big of a dose would tip it from non-lethal to lethal. So when you see lots of gas fired into an enclosed space, the lethality will increase. If it’s fired on someone who already has respiratory problems, if someone is severely asthmatic, against epileptic people or if someone is very young or very old — that’s how we get respiratory or suffocation forms of lethality. 

Then you’ve got your canister hits. This we’ve already seen some of in the United States. The reason why you’re supposed to fire these canisters at the floor and not directly at people is because they’re being shot out of these launchers, which are basically guns, at incredibly high velocities and the canisters are hard. If you get hit by something hard at an incredibly high velocity, you’re going to get injured. That can lead to lost eyes, to concussions, to internal bleeding, and, of course, to various kinds of bruising and wounds. 

The third way that people get injured or killed has to do with the pyrotechnics in the devices — the things that make the canisters or, often, the grenades explode to release the toxin. We have seen cases where, if one is throwing tear gas into a residential place, it catches fire. Back in Waco, that was actually the thing that ended up killing lots of people — incendiary tear gas. The lighter, non-lethal-but-serious injury would be severe burns from that incendiary part of the device.

In terms of transmission, the worry would be that tear gas makes you cough and sneeze and exude fluids from your body, which are all things that carry the virus and make the virus more spreadable. If you’re a medic, or a friend, and you’re caring for somebody who has been injured by tear gas or impact munitions, you’re going to come into contact with those bodily fluids, so you would have, potentially, an increased risk. In that sense, being at the protest becomes more dangerous if the police are using these weapons. 

The mass development of tear gas came after World War I. It was being used simultaneously post–World War I in a few different countries. The United States was one of those. 

The United States became a big manufacturer very early on. The guy who ran the Chemical Warfare Service, General Amos Fries, donated military samples to buddies of his from wartime who were the founders of the first US tear gas companies. They were exporting to countries who were not yet producing it in the 1920s, 1930s, when it had its first wave of taking off. Even though it was developed earlier, it didn’t get used as much until the 1950s.

There are some products that the United States uses that do come from other countries, but these are few. It mostly uses its own and exports to a number of different countries. There aren’t that many major global exporters. You’ve got Brazil and you’ve got France and increasingly China and South Korea, and Israel, a little bit. There are a few other companies here and there from other countries, but those are the big players.

After Ferguson, there was a successful lawsuit, and the police had to apologize for misusing tear gas. There was a new protocol that came out, but the protocol was basically the same as the guidelines that they should have been following in the first place, so I wouldn’t say it was a big win.

The other thing that we’ve seen is the activist campaign against Warren Kanders by Decolonize This Place. He was on the board of trustees at the Whitney Museum of Art, and there was a massive pressure campaign calling him out after the migrant caravan tear gassing, because it was his company that supplied most of that tear gas. They got staff at the Whitney on board, and then all of these artists came on board. Pressure mounted against him and he ended up having to resign. I think that kind of corporate public shaming has potential. There are not that many companies, and these companies are not that big, so it’s not like going up against Nike or Coca-Cola. 

The other main form of activism that we see that has been successful, but only on a case-by-case basis, is to “stop the shipment” — when humanitarian agencies and community organizations work with workers who are part of the supply chain to refuse to take imports or refuse to deliver products.

If you’re going out to protest and you’re expecting to be tear gassed, a proper gas mask is your best defense. There are some excellent DIY guides for how to create a gas mask. 

If you do get pepper-sprayed, water is the best thing to use. There are all kinds of formulas and ideas for formulas floating around, but the only one that has been tested against the others, and sort of proven in peer-reviewed research, is water. Take off your clothes — anything that’s contaminated — once it’s safe to do so. 

If you’re going to be handling canisters, remember that these can be explosive devices — probably not a great idea to handle them unless you are willing to take that risk or you know that they are already defused. Either way, know this is something that’s very hot, and wear protective gloves.

“Surprise” seems like too strong of a word, but the thing that maybe seems different now is that the police seem to have a greater sense of their own impunity. Not only do they not seem to be concerned that everything that they’re doing is being filmed, but they also are attacking the media. 

Consider the Occupy meme of the pepper spray cop at UC Davis: that meme, that image, was humiliating for that guy. Now we’re seeing that happen constantly, but there’s no sense of accountability or that there’s anything to be ashamed of if you’re a police officer and you’re just gratuitously using violence. 

I’m finding that perhaps the most troublesome or the most worrying part of the escalation of force. There just seems to be a brashness and an unapologetically aggressive use of tear gas, that, if not new, is certainly worrisome.