If you could read it out of people's brains, harmlessly, painlessly, etc, i think that would be fine.
Now remember, the fifth amendment protections apply in custodial settings (and similar), so you would already have to have been arrested/etc at this point (IE probable cause would have existed).
In that situation, if i could read your brain to get the truth, harmlessly, and painlessly, I have trouble seeing how that would be against the reason the fifth amendment was created (now, it may arguably run afoul of the fifth amendment as written, though things like blood tests, etc, are not considered testimonial. I don't believe literal memories would be either)
I must state that this sentiment sickens me slightly. I sincerely hope that this interpretation is absolutely unthinkable by the time technology reaches that point. I don't believe that any world in which one's thoughts and memories are not private can ever be free.
Personally, I would find it abhorrent, but that is not particularly relevant to the law.
I actually believe we are likely to need another amendment to protect us in the future, because I don't think the fifth does or would do a good job of this.
In reality, the hacker may have a perfect understanding of the current law, but disagree with it vehemently, while the lawyer's personal philosophy is actually in agreement with the hacker's statement.
Maybe? I find engineers, like a lot of intelligent people, read a lot and think this means they understand things. If they spend their time starting by reading and learning fundamentals, i'd agree with you. Instead, a lot of the time, IMHO, they read and understand particular cases in particular jurisdictions, and then take that as a truth that applies elsewhere, when it doesn't. Maybe someday i'll make a law for hackers course as a MOOC.
They also want the law to be logical, and present logical extensions of arguments (IE they want the law to be an entirely rule based system, where if all rules are memorized, all outcomes are clear) . It's certainly a necessity to be able to reason logically, but the problem is, at its core, the law is about people and situations, and not logic. Logic is just a method that is used to come up with some possible solutions to these problems, and to determine possible outcomes. It is not a god that must be followed at all costs.
IE Judges are not going to do things just because they are logical, because they are people, and not logical reasoning automatons. The law's goal is to serve a societal need, not to be theoretically sound in all cases.
This often grates on most engineers, who want bright lines and definite answers.
Anyway, this is my experience having been a "real" engineer for 15 years before/during/after becoming a lawyer, and talking to an ungodly number of engineers over the years about things.
It could be my view is skewed because of the career path i've taken :)
I do agree that there is tension between lawyers and engineers on HN, but IMHO, this is due in large part to most lawyers being able to objectively detach their feelings from their legal analysis of a situation (something one is trained to do in law school), and forgetting to mention they are doing this.
FWIW, the thing that bugs me the most is that sometimes the bright lines are more important than the soft stuff like intent and sometimes they are not and there is little rhyme or reason for why. I'm not just talking things like strict liability versus mens rea either, its just that I don't have a good example off the top of my head. Maybe AT&T vs Weev?