Hehehe, I was wondering how much interest there would be in this.
I’ll let either Bricker or Gfactor do most of the explaining, since Rick, at least, is a criminal law specialist. I can provide some basics, however.
The right embodied in the Fifth Amendment is not accurately called the right against self-incrimination. This is the text:
The government is precluded from compelling you to testify as a witness in the case against you. This preclusion extends not just to the actuality of taking the stand in court, but also to the whole concept of being forced in any way to offer testimonial evidence against yourself. This means you can refuse to answer any question, the answer to which MIGHT (subject to some limits which others will expound upon) result in testimony which could be used against you.
You are, of course, free to talk to the police if you prefer. You can voluntarily offer up any testimony or confession against yourself you want. But the government cannot legally put you under the bright lights, subject you to the rack, coerce you through threats, etc., into talking.
Why? For two basic reasons, both of which our current administration has completely forgotten (or chooses to ignore) with regard to certain other actions it takes in the name of fighting terror (which is where there is a delicious irony to this).
First, compelled testimony is of dubious value. When the consequences of not talking get large enough, people will squeal like stuck pigs, preferring the alternative, no matter how illogical that may seem in hindsight. We have plenty of cases in our jurisprudential history where people have been convicted wrongly on the basis of confessions made to crimes not committed.
Second, compelling testimony allows a government to engage in serious abuse of those who do not share its philosophies and beliefs. England’s experiences throughout the 15th through 18th Centuries were sufficient to instill in our founding fathers an understanding that government must be kept in check by strong bars to such behaviour. Indeed, this was considered so important at the federal level that the Constitution of 1787 would not have passed had this guarantee, along with several others, not been promised by the framers of the Constitution through immediate amendment.