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Some of the reasoning behind the Constitution and the Bill of Rights

From Slate.com (via MSNBC.com):

The U.S. Constitution didn't simply hatch out of an egg one morning. Like the Magna Carta, the Bill of Rights was largely conceived to correct for failures of earlier systems. In 1603 Sir Walter Raleigh was tried for treason and not permitted to cross-examine his accuser. This, it turns out, engendered unreliable evidence. The Sixth Amendment's confrontation clause was the constitutional remedy for this problem. Unremitting and unwanted prosecutorial interrogation could lead to false confessions. This made for unreliable evidence. The Fifth Amendment was, in part, the constitutional remedy for this. Years of delay prior to trials degraded evidence. The Sixth Amendment's right to a speedy trial was the constitutional remedy for this. Indefinite government detention without charges led to innocent men languishing in prison without recourse. The right to habeas corpus is thus codified in Article I, Section 9 of the Constitution to remedy this. We sometimes forget that the purpose of these and other constitutional protections is not only to let guilty guys roam free (attractive though that prospect may seem), the purpose is also to protect the quality of the evidence used in criminal trials. A conviction based on a tortured confession isn't justice. It's theater.