MILWAUKEE (Court TV) — He butchered his victims in secret for more than three years, turning his apartment into a grisly slaughterhouse filled with human heads and stripped flesh. He even took photographs of their corpses so he could later look back and relive the experience of murder.

He found teenagers and young men at bus stops, bars and the streets. He lured them to his apartment by promising drinks, pornographic videos and even money to some in exchange for sex.

Once inside his apartment, he would slip a potent sedative into their drinks, strangle them and then dismember their bodies with an electric saw.

On occasion, he ate some of their flesh.

But the secret and bizarre world of this serial killer would eventually be revealed. On July 22, 1991, two Milwaukee police officers talked to a man named Tracy Edwards. There was something odd about him. Handcuffs were dangling from one of his wrists.

Edwards told police a strange tale of a man who held him hostage and threatened him with a knife.

The man's name was Jeffrey Dahmer.

The Grisly Discovery

Edwards led the two officers to Dahmer's one-bedroom apartment at 924 North 25th Street.

They were met by Dahmer, 31, who answered the door, and an overwhelming stench. Edwards instructed police to look in the bedroom for a knife. When an officer went inside the room, he found photographs of human remains. The other officer opened the refrigerator and quickly slammed the door shut when he saw a human head inside.

Investigators found seven skulls, four heads, body parts and photos of naked and dismembered victims inside the small apartment. Human remains were found preserved in formaldehyde, and heads had been boiled. Dahmer told police how he had poured acid over flesh to dissolve remains. He had kept strips of flesh in his freezer for later consumption.

Dahmer was unmasked to the world as one of America's most notorious serial killers. He gave police a 160-page confession detailing how he lured, murdered and then dismembered the remains of his victims. He provided gruesome details of a killing spree that began in 1978 in Ohio and stretched to Wisconsin by 1991.

"It's hard for me to believe that a human being could have done what I've done, but I know that I did," Dahmer said in his confession.

In all, Dahmer admitted to killing 17 males.

But was he a manipulative killer who planned each murder in detail or simply a madman?

That was the issue facing a Wisconsin jury, which had to decide whether Dahmer would spend the rest of his life in prison or be sent to a mental hospital.

If Dahmer had been found insane in connection with the murders he committed before 1989, he could have been eligible to apply for release from a mental hospital six months after confinement. On the murders committed after 1989, Dahmer would have been up for release within a year.

Making a Case for Insanity

Dahmer pleaded not guilty to two counts of first-degree murder and 13 counts of first-degree intentional homicide. He was also charged with being a habitual criminal due to his previous conviction for sexually assaulting a child.

During a pretrial hearing in 1992, Dahmer disregarded the advice of his defense lawyer, Gerald Boyle, and changed his plea to guilty on all 15 counts, saying he was insane.

Under Wisconsin law, two trials are held in insanity cases — one to determine guilt or innocence and the other to determine whether the defendant is insane.

Since Dahmer had already pleaded guilty to the murder and homicide counts, a jury only had to decide whether he was insane.

Boyle and District Attorney Michael McCann were left to duel in court over whether Dahmer was insane, or knew exactly what he was doing in committing the gruesome murders.

The defense contended that the gruesome nature of the crimes proved that the murders were the handiwork of a madman. Boyle characterized his client as a "runaway train on a track of madness."

But prosecutors maintained that Dahmer was a manipulator who planned each murder.

Portrait of a Killer

Dahmer was born in Milwaukee on May 21, 1960, later moving with his parents to Iowa and Ohio. When he was 18, his parents divorced following a long, unhappy marriage. Dahmer attended Ohio State University for one semester and later joined the army, leaving in 1985 because of alcohol abuse.

He then moved to West Allis, a suburb of Milwaukee, to live with his grandmother. He was fired from a job there at a chocolate factory because of excessive absenteeism.

Dahmer was known to lawmen before his 1991 arrest. They had visited his apartment after one of his victims temporarily escaped. The incident occurred in May 1991. Dahmer had lured Konerak Sinthasomphone, 14, who he had met in front of a local mall, to his apartment. Once inside, Dahmer enticed him to pose for several photographs and then gave the youth a drink with a "sleeping potion," the serial killer later confessed.

After watching videos, Sinthasomphone passed out. Dahmer later told police that he had sex with the child before going out to buy more beer. As he returned from the bar, Dahmer told police that he saw Sinthasomphone staggering down the street. He went up to Sinthasomphone, but police also arrived to investigate.

Dahmer told the police at the time that the youth was a "friend" and promised to take him back to his apartment. Police escorted Dahmer and Sinthasomphone back to the apartment, but didn't investigate further.

Dahmer strangled Sinthasomphone that night, took photographs of his body, dismembered him and kept his skull as a memento.

Before that murder, Dahmer had already been on five years' probation for second-degree sexual assault and enticement of a child for immoral purposes. The victim was Sinthasomphone's 13-year-old brother.

Murderer Murdered

The jury found that Dahmer was sane. He was sentenced to 15 consecutive life terms in prison — or more than 950 years in prison.

But Dahmer never got the chance to fulfill his sentence. While imprisoned at Columbia Correctional Institute in Portage, Wis., an inmate working with Dahmer on a janitorial detail bludgeoned him to death on Nov. 28, 1994.