“Fitness to Plead” is a fundamental but understudied concept of criminal justice. It refers to a defendant’s ability to understand and participate in the legal process, a prerequisite to a fair trial. There is a need to balance the individual’s right to make autonomous decisions regarding their trial with their ability to effectively participate. The assessment of fitness to plead is carried out by psychiatrists and determined by a judge, and the costs of dealing with unfit individuals are high.