Ramesh, I would think the only credible argument that the Constitution does not require Miranda — at least for any arrest inside the United States — would be made by people whose point is to state what the Constitution requires as an abstract proposition rather than as interpreted by the Supreme Court. Assuming that we accept the premise that the Constitution requires what the Supreme Court says it requires, I don’t see how, after the Dickerson case (which I wrote about here), anyone could contend with a straight face that Miranda is not required.
Don’t get me wrong. I think Dickerson is an awful decision — and, indeed, that Miranda is an awful decision. I’d also rather see a system where a super majority of Congress can overrule bad Supreme Court decisions. But what I think doesn’t matter. The Supreme Court says Miranda is required, period.