[MisterKnowItAll]

'How about portable chemical analyzers that can be programmed to detect trace amounts of certain drugs and only those certain drugs (or explosives, etc?) That technology is very close to being available.'

That's an excellent question.

I think that under the current Court's logic, such testing would be okay as long as the substances themselves were illegal (so that the test couldn't reveal that you had some legal-under-certain-circumstances substance for a lawful purpose) -- and, of course, as long as the test wasn't administered under circumstances that failed to meet Constitutional standards in some other way.

Under those precise circumstances -- and only those -- I'd probably agree. I don't think the purpose of the Fourth Amendment is to keep actual criminals from getting caught.

[NJ_gent]

"I don't think the purpose of the Fourth Amendment is to keep actual criminals from getting caught."

I agree with that; I think its purpose was to prevent spot-checks by government agents who could use such authority in a targetted way to harass citizens and increase government power and control. I also think it was intended to operate under the idea of 'better to let 10 guilty men go free than put 1 innocent man in prison', etc.

[green iguana]

I don't think the purpose of the Fourth Amendment is to keep actual criminals from getting caught.

Well, in that case it's only a few years away that we should all expect to have the air emanating from our cars scanned during every legal traffic stop. See sensing device