....if there’s a real, imminent threat.

In some of these cases, it seems like the officers could have tried to de-escalate the situation while keeping these options in reserve in case that failed. The choices don’t have to be either immediate compliance or overwhelming force.

Even with animals—-where the use of drugs is a lot less ethically fraught—-ketamine isn’t necessarily the first option.

Sure, the indications for using it can be clarified. EMS would go for chemical restraint (i.e. ketamine) for someone where "excited delirium" is suspected. This doesn't mean literally anyone being ornery with the police - and generally we aren't even involved in those calls. A person in a normal state of mind won't break their arms or dislocate their shoulders when they're put in handcuffs. Someone who took too much meth very easily could.

In this case, it says they used 500 mg of ketamine in an injection, so basically they killed him with an excessive dose. Even though ketamine might have a higher LD50 you can't compare drugs without knowing the dose they are using.

https://en.wikipedia.org/wiki/Death_of_Elijah_McClain

500mg? Might as well just shoot (someone) in the head. Total unprofessionalism.

"normal" dose would be something like 10-30mg

My protocols for excited delirium say ketamine 100-200mg IV/IO or 200-400mg IM.

That doesn't sound like a very safe protocol to follow considering the max dose in a controlled environment for depression treatment is 1mg/kg.

It's worth noting "excited delirium" is a controversial diagnosis.

True. Administering many drugs without the proper knowledge can be dangerous.