Before a serial killer strikes for the first time, his fantasies normally focus on committing the murder. After his first attempt, the killer starts focusing on committing future murders more efficiently and successfully. But what are the motives of killing innocent people?

According to the FBI, there are seven categories of motivation: anger, criminal enterprise, financial gain, ideology, power or thrill, psychosis and sexual desire.


Killers who display rage or hostility towards a certain subgroup of the population or with society as a whole.

Criminal enterprise

Those who benefit in status or monetary compensation by committing murder that is drug, gang, or organized crime-related.

Financial gain

A motivation in which the offender benefits monetarily from killing. Examples of these types of killers are black widows, robbery homicides, or multiple killings involving insurance or welfare fraud. Usually, the victims are family members or close acquaintances. A hitman is considered a serial killer.


Ideology killings are oriented to a specific individual or group, in order to further their goals and ideas. It may be terrorist groups or one or more individuals who attack a specific racial, gender or ethnic group.

Power or thrill

Power or thrill seekers are killing for empowerment and/or excitement when they kill. It often fulfills their desire for power and control.


Psychosis-driven killers are suffering from psychotic breaks with reality and often are compelled by the Devil or God. This kind of killer may suffer from visual hallucinations and paranoia with grandiosity or delusions.

Sexual desire

Sexually-based killers kill to fulfill their sexual needs or desires. There may or may not be overt sexual contact reflected in the crime scene.

Most often used and most widely accepted is four-fold typology, developed by criminologists Ronald Holmes, Stephen Holmes, and James De Burger.

The typology consists of two general groups of act-focused and process-focused killers, which are separated into four different categories: visionary killers, mission-oriented killers, hedonistic, and power or control killers.

Act-focused killers

An act-focused killer kills quickly and does it only for the act itself. There are two categories of killers within this group – visionary and mission-oriented.

Visionary killers

Let’s start with the visionary killers, which are often classified as act-focused, demon or God-mandated psychotics. As mentioned before, they are ones who are killing because of mental illness. They are suffering from psychotic breaks with reality and often are compelled by the Devil or God.

This kind of killer may suffer from visual hallucinations and paranoid, grandiose, or bizarre delusions.

Visionary killers select absolutely random victims; they don’t have any logical order or agenda of their killings because they’re driven to kill by the internal or external voice they imagine.

They don’t have a specific victim type unless the voice or visual hallucination mandates it.

“Son of Sam” David Berkowitz is a good example of the visionary killer. He believed that Satan was ordering him to kill. He was convinced that Satan would set him free of his loneliness and emotional pain through the act of murder. But despite his initial euphoria, Berkowitz was still empty and unfulfilled.

Ed Gein murdered women who looked like his mother prior to making his “woman suit.” He ate one of his victims to preserve his mother’s soul who he believed was living inside his body.

Another example is Herbert Mullin, who killed thirteen people in California in the early 1970s. He believed that he was taking orders from God and what he did was just obeying his commandments.

Mission-oriented killers

Mission-oriented killers generally aren’t psychotic. They want to make the world a better place to live according to their own attitude. They think that they need to get rid of people who shouldn’t be a part of society or even walk on the Earth along with them.

They may target homosexuals, prostitutes, or people of different ethnicity or religion. By doing that, they believe they are doing the world a favor by killing unwanted or “dirty” people.

Mission-oriented killers are huge perfectionists and plan their killings with great precision. Because of that, they kill their victims quickly and efficiently.

An exclusive example of a mission-oriented killer is Joseph Paul Franklin, who killed black males who had white female companions. He hated mixed-race couples, which he called MRC’s. The only difference from the ordinary mission-oriented killer’s portrait is that Franklin was a paranoid schizophrenic who was not fit to stand trial.

One of the world’s most famous criminals, Charles Manson, might also be considered as a mission-oriented killer. He actually never killed anyone but was persuasive and manipulative enough to force others to do that for him. Manson planned to create a race war between the white and black people, so the members of his “Family” would take over the world because of the confusion created. Manson would be considered a serial killer by proxy according to several serial killer experts including Dr. Peter Vronsky, RJ Parker, and Dr. Scott Bonn.

The unidentified monster of Whitechapel, Jack the Ripper, could fit in this category too because he possibly had a particular hatred for women. In his letters sent to the police, he gave a good sense of it by calling his victims “whores.”

“The Unabomber” Ted Kaczynski fits this category as well.

He targeted people and institutes that promoted the progress of modern technology by mailing them numerous homemade bombs. Three of his twenty-six targets were killed.

Kaczynski was considered as a strong suspect in the Zodiac Killer’s case, but he was cleared without any strong evidence.

Process-focused killers

Second, process-focused killers group, who kills slowly and enjoys the act of torturing, is separated into hedonistic and power or control killers categories.

Hedonistic killers

Hedonistic killers are thrill seekers and those who simply kill for pleasure. Forensic psychologists divided hedonists into three subtypes: lust, thrill and comfort killers.

Lust killers

Lust killers kill for sexual pleasure. It doesn’t matter if their victims are alive or if they’ve been killed, they’re doing it for sexual gratification. Gary Ridgway re-visited his victims and had sex with the corpses as they were rolling in maggots.

Fantasy plays a large role in their killings too. They often use weapons that require close contact with their victims, in most cases, bare hands or knives. They’re highly stimulated by torture and the mutilations that they perform on their victims. As the killer escalates and gains more experience, his cooling-down period often decreases as his level of required stimulation and confidence increases.

Most of the lust killers are expert stalkers and manipulators, using charm to lure their victims into a trap where they’re powerless.

Most people give the more notorious lust killer’s credit to Jack the Ripper, who was believed to achieve sexual pleasure by mutilating his victims and taking out their organs. But in my opinion, Jeffrey Dahmer deserves it more. Ripper was never caught and no one has proof of who he was. At the moment, after more than 120 years, it looks like his motives will remain a mystery and will be shrouded in speculation.

Unlike the Ripper, Jeffrey Dahmer admitted in an interview that lust played a big part in his killings. Once Dahmer said “the killing was just a means to an end. That was the least satisfactory part. I didn’t enjoy doing that. That’s why I tried to create living zombies with acid and the drill.”

Thrill killers

Thrill killers kill just for the pleasure of killing. Their main motive is to induce pain or terror in their victims. They’re addicted to the adrenaline rush they get from the hunt, killing their victims, and evading the law.

Most of the time, their victims are complete strangers, but they may stalk people for a while before killing them.

Thrill killers believe that “practice makes perfect” and most of the time it becomes real. Their killing career can last for a very long time; they can become more successful at killing, and they often try to commit the perfect crime. Killers can lie low for a very long time, which causes a possibility of a “spree-killing,” but that’s more commonly behavior of less intelligent thrill killers, which often leads to their capture.

Henry Lee Lucas is one of the most notorious thrill killers, who traveled around the states killing people. He confessed to hundreds of unsolved murders, which were attributed to him and classified as cleared up.

However, he was only officially convicted of eleven killings.

The Zodiac Killer, whose identity is still unknown, is another example of a thrill killer. Zodiac, in his final letter to the San Francisco Chronicle, claimed to be responsible for 37 killings, but only 5 were assigned to him.

For this kind of killer, the process of preparing to kill and the killing itself is the most fulfilling thing in the world.

The attention he got from sending taunting letters and cryptograms to newspapers and police gave him an additional boost of pleasure.

Comfort killers

And the last sub-type of hedonistic killers is comfort killers, who, as I mentioned before, kill for profit. After each murder, the killer usually waits for a period of time before killing again to avoid any suspicions by family or authorities. Victims are often poisoned, most notably with arsenic.

Most female serial killers fall into this category. For example, Blanche Taylor Moore was convicted of killing her boyfriend when she poisoned his food with arsenic. Later, she was suspected of killing three more people and nearly killing another in the same manner. It was believed that she was driven to kill for the financial gain.

Another example is Dr. H.H. Holmes, who built a three-story hotel specially designed for killing.

Holmes took out insurance policies on many of his hotel guests before he killed them.

Diana Lumbrera murdered her own six children within a fourteen-year time frame in order to collect insurance money.

Power or control killers

The four-fold typology finishes with the last process-focused power or control killers, who are driven by the power they have over their victims. They enjoy torturing their victims, which is sexually attractive to them, but the process of having complete life or death control is more satisfying. The killer may rape the victim, but it’s not motivated by lust, it’s just another form of domination over the victim.

Ted Bundy, who was one of the most dark-minded killers, fits in this category. He stalked, raped, killed, and performed necrophiliac acts (sex with a corpse) on his victims. With over thirty of them confirmed, he’s one of the most prolific serial killers in the United States.

One of the reporters who interviewed him said, “Ted insisted that violence was never an end in itself and sex was almost perfunctory. Gratification lay not in the assault but in the possession of the victim.”

“Green River Killer” Gary Ridgway, “Killer Clown” John Wayne Gacy and “BTK” Dennis Rader fit into this category too.