In the Polish legal system, the institution of an expert witness was established to ensure the proper functioning of law enforcement agencies and the judiciary. However, the practice of the judiciary shows that the lack of competence, experience, and liberal regulations on the selection of experts, moreover, the lack of tools to verify their skills, are the main sources of problems with experts. The aim of the article is to catalogue the key competencies that an expert in forensic genetics should possess in relation to the currently applicable regulations as well as the draft act on expert witnesses. In the final part of the article, conclusions are presented that should be considered during the legislative work on the provisions normalizing the operation of experts during legal proceedings.