Since it can be proved that your uncle is not having a stable mental health, this can be a reason to get him out of the crisis.
To stand trial, a defendant must be fit. If a person has committed an offence under the Criminal Code and suffers from a mental health problem, his or her fitness to stand trial may be questioned. The term "fit to stand trial" refers to the mental state of the defendant at the time of the legal proceedings.
The insanity defense, also known as the mental disorder defense, is an affirmative defense by excuse in a criminal case, arguing that the defendant is not responsible for his or her actions due to an episodic or persistent psychiatric disease at the time of the criminal act.