We're awaiting confirmation from UC-Davis police, but after examining photos and videos of the incident, this is what we believe campus police used against the Occupy Wall Street protesters at UC Davis this weekend. It's nasty.

This here is the MK-9 stream canister, one of the strongest available forms of pepper spray. How peppery your spray is can be measured by its Major Capaicinoid content, and you can determine the amount based on the coloring of the can. In this case, cops appear to have used a 1.3 percent solution. The only time a spray is more potent? When it's meant to stop a freaking bear.

Assuming it's 1.3 percent—or even if it was the slightly less-intense 0.7 percent, as some pictures indicate—that's some heavy duty stuff. It's much stronger than the 0.2 percent that's authorized for tactical deployment, making this a sizable hammer for this particular nail. And even if it were an appropriate dose, it was sprayed at near point-blank range. The recommended minimum distance? Six feet, and it remains effective at 18-20 feet.


At that high-level dosage, the burning, boiling eye sensation and difficulty breathing would obviously be amplified. Any form of pepper spray can be serious trouble—even lethal—for someone with asthma or a heart condition, and we're talking the stuff the Marines train with here.

So that's one more bizarre layer to the already-surreal UC0Davis scene: the spray used on kneeling protestors was strong enough to take down a bear. [Defense Technology]


Update: Sharp-eyed commenter marinsmostwanted found a photo of the canister that seems to definitely show an orange band, which would make this 0.7 percent MC. We're very relieved, in retrospect, that no bears showed up to Friday's rally.