Well, around here the cops know who has guns, as well as whether they're known to be a bit crazy. The police are also usually not treated like an invading army, so it's apples for oranges.
I'd at least suggest holstering the weapons until they're needed and weighing the probability of encryption against the probability of forceful self-defense, case by case. If for some reason there's reason to believe that the person is working next to both a loaded gun and an encrypted disk, sure, treat it as a hostage situation and call swat or the wiretappers in. I don't think that's the norm, though.
"The police are also usually not treated like an invading army"
(emphasis mine)
This shows you don't understand the point (I'm not so much talking about this specific case or even raids on computer criminals anymore, rather in general). The exact point is that sometimes it does happen, but you don't know why. That's why you need to treat every opportunity, no matter how minute, as more dangerous than it actually is, or than you actually think it will be, because the consequences are so out of balance.
Let me put it this way: do you feel that 500 unnecessarily forceful raids, each destroying a door and 2 pieces of furniture, and taking a night of sleep away from 500 individuals, are better or worse than 1 policy officer shot in the leg (not even deadly)?
I think the shot wound is worse, and therefore wouldn't mind authorizing a raid even when I'm not 100% sure there is acute danger. Actually I'd authorize when there's even just a 1% chance of forceful resistance with a knife.
(the trade off may get different when suspects are harmed in the raid, I'm assuming sufficiently trained police people)
"and weighing the probability of encryption against the probability of forceful self-defense,"
This I don't understand. I'm quite sure no suspect will try to fire at policeman with their Truecrypt USB drive.
"If for some reason there's reason to believe that the person is working next to both a loaded gun and an encrypted disk"
The 'and' between 'loaded gun' and 'an encrypted disk' should be an 'or'. Just one of the two is enough to warrant force.
Assuming that, well that's already the trade off being made. I just think you underestimate the amount of criminals using encryption. Even if only 5% of them do use it, that already makes it likely enough that any random one (because remember, before you enter you don't know what you will find) will use it to warrant force. QED.
I considered not using that word (usually), but decided I don't know enough to remove all weaseling. I didn't intend it to be taken as representative of my understanding. However, from your exposition, it seems fitting.
I'm firmly against all examples of zero tolerance. From your example, I think 500 disturbances of peace and destructions of property is far worse than one realization of a work hazard. I would draw the line at perhaps 10. There used to be a principle that it is better to let 10 guilty men walk than convict a single innocent - do you not subscribe to this either?
I'll clarify what I meant with the juxtaposition of encryption and forceful resistance:
encryption is a justification for occupied searches, since you need to confiscate the electronics while they are unlocked. I don't know if that's actually done, though, since it's my understanding that the electronics are routinely removed from the premises and disconnected in the process. This scenario does not warrant the use of any force.
Armed defense is a justification for surprise arrests, since you need to arrest the suspect when they're not in defensive positions. A good time to do this is during ingress or egress. This situation does not warrant the use of devastating force.
The only reason to assault a dwelling with shock tactics would be to capture armed resistance in the act of handling evidence. Perhaps that's an actual worry for the FBI, who seem to assume all of their suspects are paramilitary, but I don't think it's a reasonable worry in the majority of cases, even the ones handled by the FBI.
I hope you now understand better where we disagree.
I'd at least suggest holstering the weapons until they're needed and weighing the probability of encryption against the probability of forceful self-defense, case by case. If for some reason there's reason to believe that the person is working next to both a loaded gun and an encrypted disk, sure, treat it as a hostage situation and call swat or the wiretappers in. I don't think that's the norm, though.