Fri bevisprövning eller förgiftad frukt? - Om tillåtligheten av olagligt anskaffad bevisning enligt svensk rätt och EKMR sett i ljuset av amerikansk rätts exkluderingsregel

Sammanfattning: In Sweden, the free assessment of evidence has been a strong principle of procedural law ever since the legal proof theory of the inquisition was abandoned. As a consequence, no exclusionary rule has developed, which means that all evidence has to be admitted at trial, regardless of the way in which it has been gained. In contrast, American law has developed a distinct exclusionary rule. Consequently all evidence that is gathered with illegal methods has to be excluded at trial since the use of such evidence would deprive the defendant of his or her constitutional rights. This is also true, with regards to derivative evidence that is a product of the illegally produced evidence, under a legal institute that has become known as “the fruit of the poisonous tree doctrine”. It could be argued that the different ways in which evidence is handled in Sweden versus USA express different views concerning the question of what ought to be the purpose of a criminal process. While the system with free assessment of evidence serves to find the material truth, it could be argued that it – when admitting illegal evidence – does so, at the cost of judicial integrity and at the cost of due process. Conversely, it could be claimed the US exclusionary rules cherish the values of due process, but at the expense of an effective crime control. Having studied both systems and the way in which they relate to the question of that ought to be the purpose of the criminal procedure this essay will direct its attention towards one case from the Swedish Supreme Court, NJA 2011 p. 638, and one case from the European Court of Human Rights, Gafgen v. Germany. Both cases shed light on the question of whether or not derivative evidence should be admitted at trial. The author ultimately argues that these cases indicate there is a subtle tendency towards a change with regards to the perception of how illegally gathered evidence should be treated.