The paper discusses the problem of admissibility of scientific and especially neuroscientific evidence in the Polish legal system. In the first part of the paper there are discussed the methods of neuroimaging and there use in legal proceedings. Then, the author focuses on the criteria of admissibility of scientific evidence in Polish and American legal system. In the next part, the author attempts to identify the threats connected with the misuse of the neuroimaging evidence in the courtrooms. The last part contains a set of suggestions on how to change the Polish legal system in order to prepare it for the use of the neuroscientific evidence.