When a judge is looking for responsibility and when geneticists themselves express the effect of genes in terms of responsibility, some confusion may be expected [6]. In taking a decision, a judge must decide whether there is enough evidence for responsibility, and this is a probabilistic process; however, she/he judges about the probability that the purported evidence has been causal in determining the criminal behavior, i.e., that the evidence ensured at the time the crime was committed that the individual had limited freedom of will, hence responsibility for her/his actions. The judge must decide about juridical evidence, and genetic evidence is currently not such, it is only biological evidence.