EN
Giving evidence by a witness is an obligation of everybody who is summoned by court. However, there are exceptions to this rule - one of them is the right to refuse testimony. In the Polish penal trial the right to refuse testimony has been shaped as a privilege of a witness summoned by court to testify in the case where the accused is the witness' next-of-kin. The assumption here is that thanks to this the witness does not have to choose between his next-of-kin's good and the obligation to make truthful testimony, which may result in the accused person's conviction. However, there is also another object that is protected by the right to refuse testimony, namely a penal trial. Allowing the witness to refuse testimony reduces, at least theoretically, the cases where material truth is not achieved due to false testimony. But is this aim always achieved? The purpose of this paper is to outline these problems and to look at possible benefits. The results of the conducted survey indicate potential threats to achieving truth in a penal trial. The results show that a considerable number of respondents would rather choose making false testimony to avoid suspicions as to their motives to refuse testimony.