For those readers who have not experienced tear gas firsthand, please know that it will mess you up. It will knock you down. It will close your throat and burn your eyes. It has caused the deaths of scores of humans around the world.

It should not be used by any U.S. police departments, under any circumstances.

Tear gas is a chemical agent known to cause respiratory failure, heart attacks, and miscarriage. It’s considered so inhumane that its use in warfare was banned under the Chemical Weapons Convention of 1993.

That agreement was signed by almost every nation on earth, including the United States, so the fact that it’s used on U.S. citizens for crowd dispersal is appalling.

At an anti-Trump protest in Phoenix a few years ago, hundreds of us got tear-gassed by police at 8:30 pm after a day of peaceful demonstration. There was no provocation that warranted its use.

If you want to hear what it was like, here’s the tape of me trying to cover the protest while inadvertently taking a lungful of yellow gas.

Note that during the tape, I’m trying to report on a phalanx of cops closing in on an unarmed couple. I lost them in the gas and don’t know what happened to them. There were no serious injuries reported at this protest, so I assume they were not harmed.

But the tape shows the confusion and horror on the part of the demonstrators, some of whom were elderly and crouched on the side of the road, trying to recover. You can hear a group stopping to help an older woman who is disoriented and whose eyes are burning. Almost without exception, tear gas is used without warning, so the most vulnerable have no chance to get out of harm’s way.

If you live in a city or state that allows the police use of tear gas, do what you can to make it illegal. If you’re out there in these next days and weeks, and you see the yellow gas streaming from the canisters, don’t trifle with it. It is no joke.