A delusion is a belief held with strong conviction despite superior evidence to the contrary. As a pathology, it is distinct from a belief based on false or incomplete information, confabulation, dogma, illusion, or other effects of perception.

Delusions typically occur in the context of neurological or mental illness, although they are not tied to any particular disease and have been found to occur in the context of many pathological states (both physical and mental). However, they are of particular diagnostic importance in psychotic disorders including schizophrenia, paraphrenia, manic episodes of bipolar disorder, and psychotic depression.

Perry v. Louisiana, 498 U.S. 38 (1990), was a United States Supreme Court case over the legality of the forcibly medicating a death row inmate with a mental disorder in order to render him competent to be executed.

Joseph Kallinger (December 11, 1935 -- March 26, 1996) was an American serial killer who murdered three people and tortured four families. He committed these crimes with his 13-year-old son Michael.

Leonard Lake (October 29, 1945 -- June 6, 1985) was an American serial killer. He often used the alias Leonard Hill. The crimes he committed with Charles Ng became known when Lake committed suicide by taking a cyanide pill shortly after being arrested for a firearms offense.

Colin Ferguson (born January 14, 1958) is a mass murderer who was convicted of murdering six people and injuring nineteen others on the Long Island Rail Road in Garden City, New York.

On December 7, 1993, as the train pulled into the Merillon Avenue Station, Ferguson pulled out his gun and started firing at passengers. He killed six and wounded nineteen before being stopped by three of the passengers: Kevin Blum, Mark McEntee and Mike O'Connor. Ferguson's trial was notable for a number of unusual developments, including his firing of his defense counsel and insisting on representing himself and questioning his own victims on the stand.

Ferguson was convicted on February 17, 1995, of murder for the deaths of the six passengers who died of their injuries. He was also convicted of attempted murder for wounding nineteen passengers. As of 2013, he is serving his sentence of 315 years and 8 months to life at the Upstate Correctional Facility in Franklin County, New York. His earliest possible parole date is August 6, 2309.

The Wakefield massacre occurred on Tuesday, December 26, 2000, at Edgewater Technology in Wakefield, Massachusetts, United States, during which the gunman, Michael "Mucko" McDermott, an application support employee, shot and killed seven co-workers.

He was found by police sitting calmly and stated that he didn't speak German. At trial, he stated that he was born without a soul and that God had allowed him to earn a soul by traveling back in time to kill Nazis. However, the prosecution asserted that the killings were motivated by his employer's garnishing of his wages to the IRS, to pay back taxes that he owed.[citation needed]

The weapons he used were an AK-47 variant, a 12-gauge shotgun, and a .32 caliber pistol. He fired off a total of 37 rounds, shooting his victims in the back of the head repeatedly. Police would later find a .460-calibre Weatherby Mark V rifle at the defendant's work station.

Film Duration: 45 min