Abstract
The legitimateness, purpose andscope of the forensic psychological opinion in civillawsuits concerning validity of statement of will,including validity of wills, are analysed. Theauthors compare the criteria for mental capacity for informed and free taking and expression of will, laid out in appropriate acts of parliament,with the criteria adopted in such cases by forensicpsychiatrists and they analyse the possible role of psychological expertise in the indication of suchcriteria, their definition and negotiation betweenthe court and experts called in to evaluate the testator's mental condition.