Rah Self-Incrimination
The more I think about law, the more I see arbitrary historical accidents enshrined into unquestioned dogma. Consider: we require people to answer questions by police or courts investigating crimes, without privacy excuses and without compensation for lost time. We apparently estimate the value of investigating crime to outweigh such costs. Except, we exempt criminal suspects from answering questions! (We also exempt folks statusfully related to suspects.) Yet if anyone should give up time and privacy to help investigate a crime, it is the suspects.
Here is one account of this history of this rule:
The right was created in reaction to the excesses of the Courts of Star Chamber and High Commission … 1487-1641. These courts utilized the inquisitorial method of truth-seeking … sufficient “proof” came from browbeating confessions out of the accused. These courts required the accused to answer any question put to him, without advance notice of his accusers, the charges against him, or the evidence amassed. … By the 18th century, English law provided that neither confessions coerced during the trial nor pretrial confessions obtained through torture could be used. …. The U.S. Supreme Court has expanded the Fifth Amendment to apply … to “any other proceeding, civil or criminal, formal or informal, where his answers might incriminate him in future criminal proceedings.” (more)
Somehow, many think this history shows that today a right not to self-incriminate keeps police from torturing confessions out of suspects. But to prevent torture, we should just have rules against torture. A further rule against self-incrimination can’t prevent torture for the simple reason that we let people waive their right not to self-incriminate. If police can force confessions via undetected torture, then police can also use undetected torture to force people to waive their right against self-incrimination!
The following video argues that if suspects must answer police questions, then police can find enough mistakes in what most anyone says to make them seem guilty:
The detective in this video also says that if he follows most anyone long enough he can catch them breaking a law. But if true these seem grounds for raising standards of proof at trial, and for disclosing at trial the amount of questioning or following done.
We don’t want to protect people from being framed by the police merely by making police work generically harder. For example, requiring police to always hop on one foot, or to constantly sing the national anthem, would surely make it harder for police to frame folks, but simply by making it harder for them to do anything! The rule against self-incrimination seems yet another arbitrary handicap, making police work harder overall, without discouraging bad policing more than good policing.
Rather than giving arbitrary handicaps, we’d do better to just reduce the size of the police force and budget, and to restrict police in ways that more directly distinguishes good from bad policing. Having suspects answer police questions does not so distinguish, being just as much a part of good as bad policing.
Without the 5th this puts lawyers in a very touchy position.
As lawyers are prohibited from suborning perjury they can't advise an unsophisticated client to 'not remember' what happened or suggest you lie. So without the 5th really all counsel can do is try and calm you down especially since they will be unfamiliar with the evidence at that point.
Given that many arrests occur after fairly intense situations (someone is shot, a robbery happens, police bust a drug deal etc..) and the person arrested is often intoxicated or otherwise compromised without the 5th you face the prospect of facing determined inquisition to get you to admit guilt or contradict yourself, including application of lies and tricks, while in a compromised state while the jury only receives the transcript.
I think you miss three important considerations here:
1) In the US legal system the prosecution can bring up past behavior and other information about a testifying witness to impeach their honesty that would otherwise be inadmissible at trial. For instance past convictions for fraud or even perjury would generally be inadmissable at a murder trial but if the defendant could be forced to testify the prosecutor could pull in these charges to paint the defendant as a bad guy under the guise of impeaching his credibility.
Also it's well known by defense attorneys that if the defendant takes the stand and the jury doesn't find his testimony convincing/believable they will usually convict even if the prosecutor's evidence would otherwise be judged not to meet the standard of proof.
2) We generally feel it's cruel to impose additional punishments on someone for insisting on their innocence or that of a spouse. Furthermore, plea bargains are already far too easily used to coerce a guilty plea from an innocent suspect. Should the prosecutor have the additional power to force them or their spouse to testify and impose punishment for perjury if they insist on their innocence it would create even greater risk for false guilty pleas.
3) People don't appreciate the extent to which our recollections and beliefs are inferred from context and the assurances of others. Given the ability of the police to lie during interrogation without the right not to speak suspects could be put at a considerable disadvantage by police seeking to ellicit false statements of recollection ('We have you on film at the grocery store at 10pm could you have gone out after drinking and forgotten it? Well I guess that's possible. Used in court to show the suspect isn't sure whether he was really home the whole time and suggest he was so drunk he forgot killing the victim.)
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However, it is true that we give undue protection against self-incrimination relative to the other protections we offer. Far more important IMO is restrictions on acceptable plea bargains to prevent false confessions for fear of being convicted by an unsympathetic justice system. Also restrictions on police lying to elicit statements.