Apparently the idea that previous convictions should not be allowed as evidence is a quirk of the American justice system.
I think it should be allowed as evidence.
In the majority of legal systems in the developed world, triers-of-factare routinely made aware of the prior convictions of the accused. In theUnited States, the admission of evidence of prior crimes is much moredifficult, facing a multitude of hurdles. According to Federal Rules ofEvidence (FRE) Rule 404, prior crimes categorically cannot be used toshow character in order to prove “action in conformity therewith” or toshow a propensity to illegal acts (unless defendant triggers a discussion ofcharacter), and they must also pass the Rule 403 balancing test, which rulesout such evidence if the judge concludes that it is substantially moreunfairly prejudicial than probatory. If a defendant takes the stand, priorconvictions can be used as evidence that he is a liar under Rule 609—subject to the exceptions spelled out in Rule 404(b)—but generally not asevidence that he committed the crime with which he is charged.2The exclusion of prior crimes is not an occasional quirk of theAmerican legal system. It is the rule rather than the exception. In nine outof ten jury trials of defendants with prior convictions in which thedefendant does not testify, the jury never learns about the prior convictionsthrough evidence.3Certain aspects of American evidence law—and considerableAmerican evidence scholarship—are founded on a widely-shared set ofbeliefs concerning the admission of prior crimes of the defendant.
Most ofthese beliefs are predicated on hypotheses about the perverse inferentialpsychology of jurors when it comes to evaluating prior crimes information.Others are founded, not on presumed juror psychology, but on dubiousepistemic hypotheses about the probatory strength of prior crimes evidence.Moreover, there is substantial handwringing about the difficult choicedefendants face about taking the stand in their own defense: if a defendanttakes the stand, he risks being destroyed by his prior convictions; if he doesEven in trials where the defendant takes the stand, thejury learns of his priors only about half the time. Since more than half ofdefendants who go to trial have prior convictions, we are talking aboutmassive exclusions of prima facie relevant evidence.
https://scholarlycommons.law.northwestern.edu/cgi/viewcontent.cgi?article=7395&context=jclc
