The main cause of death for these patients was starvation, as caretakers did not supply the patients with adequate food, likely as a form of torture and a method of sedation. Because mentally ill patients were kept secluded from the outside world, the large number of deaths went unnoticed by the general public. After the end of Allied occupation, the National Diet of Japan passed the in 1950, which improved the status of the mentally ill and prohibited the domestic containment of mental patients in medical institutions. However, the Mental Hygiene Act had unforeseen consequences. Along with many other reforms, the law prevented the mentally ill from being charged with any sort of crime in Japanese courts. Anyone who was found to be mentally unstable by a qualified psychiatrist was required to be hospitalized rather than incarcerated, regardless of the severity of any crime that person may have committed. The Ministry of Justice tried several times to amend the law, but was met with opposition from those who believed the legal system should not interfere with medical science. After almost four decades, the was finally passed in 1987. The new law corrected the flaws of the Mental Hygiene Act by allowing the Ministry of Health and Welfare to set regulations on the treatment of mental patients in both medical and legal settings. With the new law, the mentally ill have the right to voluntary hospitalization, the ability to be charged with a crime, and right to use the insanity defense in court, and the right to pursue legal action in the event of abuse or negligence on the part of medical professionals. By 1936, killing of the "physically and socially unfit" became accepted practice in Nazi Germany. In the 1940s, the abuse of psychiatry involved the abuse of the "duty to care" on an enormous scale: 300,000 individuals were sterilized and 77,000 killed in Germany alone and many thousands further afield, mainly in eastern Europe. Psychiatrists were instrumental in establishing a system of identifying, notifying, transporting, and killing hundreds of thousands of "racially and cognitively compromised" persons and the mentally ill in settings that ranged from centralized mental-hospitals to jails and death camps. Psychiatrists played a central and prominent role in sterilization and euthanasia, constituting two categories of the crimes against humanity. The taking of thousands of brains from euthanasia victims demonstrated the way medical research was connected to the psychiatric killings. Germany operated six psychiatric extermination centers: Bernburg, Brandenburg, Grafeneck, Hadamar, Hartheim, and Sonnenstein. They played a crucial role in developments leading to the Holocaust.