What, exactly, is a serial killer?

What does someone have to do to be labeled a “serial killer”? How is it different from a mass murderer, or just a regular murderer? I’ve tried search engines looking for this answer, but all I’ve been able to find are those “I’m 15 years old and I like death so here’s me talking about serial killers because I’m so weird” web pages. Plus, the Woodside Killer scares the hell out of me and I hate accidentally finding information on him.

A serial killer has a pattern of killing people over a period of time. They usually kill to satisfy a sexual or psycological urge. After killing, that urge might be sated for days, weeks, sometimes even years before it needs to be satisfied again.

A mass murderer is someone who kills several people over a short period of time, often claiming many people in a single incident. The motivation for most mass murderers is severe psychotic delusion or the need to vent uncontrolable rage.

A mass murderer has a better chance of getting off on an insanity plea than does a serial killer.

Ursa summed it up pretty well. Here’s a website that chronicles the exploits of both:
http://www.mayhem.net/Crime/

Also, victims of a serial killer usually have common characteristics, like all blondes in the northeast part of the city or all previously employed as Burger King or SDMB members who all have “girl” as part of their screen names.

This victim profile helps a little in two ways: authorities can focus on the target group, and potential victims can try to “blend out” of the killer’s preferred target group.

The common characteristic is what links the victims in a serial fasion. (Probably from “serial number” which is a number that increments on items of the same brand & model.)

An important point was noted. It was also brought up in a PBS show. The serial killer has a sexual] element in it. They showed how that in many cases it was suppressed but it is there

Well, I hope opus quelled your fears. :rolleyes:

Actually, a serial-killer, back when there were soap operas on radio, was a circuit that turned the radio off when these programs came on – in order to facilitate the wife’s getting the housework done.

Ray (Even massively parallel machines can get things done in very quick sequence. Shut up and eat your serial!)

Let’s just say that I kill two blonde men on two seperate occasions a week a part, and I leave both their bodies near interstate 40. Does this make me a serial killer? I mean, I have a pattern, but does only two victims make me a serial killer, or does it have to be more than that?

That would qualify you. You’re not planning anything, are you? Nickrz will have to shut down this thread.

Why? Aren’t they both insane?

The legal definition of the term “insane” is usually whether one can tell the difference between right and wrong. It’s easier to prove temporary insanity than it is to prove that one could go on killing for days, weeks or years without once questioning the morality of the acts. The very fact that a serial killer tries to ellude the law and cover his tracks is usually proof enough that he realizes what he is doing is wrong.

A mass murderer who goes on a rampage often will not actively try to make a secret of his crime because often he doesn’t realize or even consider what he is doing is wrong. A lot of these guys are caught soon after the crime or are found to have committed suicide after realizing what they have done.

For recent well-known examples, the guy who shot 5 people in Pennsylvania thia last week is a mass-murderer. The railroad killer that was making headlines a few months ago is a serial killer.

FWIW, the railroad killer is set to plead insanity in his upcoming trial of a Houston doctor’s murder.


Sue from El Paso

Experience is what you get when you didn’t get what you wanted.

Most “standard” definitions of a serial killer state that the killer must kill three or more individuals. This is not always the case, as Ed Gein is usually referred to as a serial killer and he only (as far as anyone knows) killed two people.

Another qualification that must be filled to be called a serial killer (and the actual defining difference between serial killers and mass murderers) is a cooling off period between crimes. Often serial killers will experience remorse in these “down-times” (Jeffery Dahmer) and many psychologists charcterize it as almost a post-coital depression.

BTW, I’m not 15, I’m not interested in death (by itself) and I am not weird (not that weird anyway), but I am very interested (some say obsessed) with serial killers. I have many, many books and I enjoy studying the psychological profiles.


I have a hobby. I have the world’s largest collection of seashells. I keep it scattered on beaches all over the world. Maybe you’ve seen some of it.

Cereal Killers: Tusk, the Elephant is after Snap, Crackle, and Pop! They took away his job with Cocoa Krispies! (Well, ok, somebody HAD to say it!)


“They’re coming to take me away ha-ha, ho-ho, hee-hee, to the funny farm where life is beautiful all the time… :)” - Napoleon IV

Well… yes, but there’s more.

There are actually in most states one of two standards for legal insanity. One is, as you suggest, that a criminal defendant is considered to have been insane if, at the time of an act, if he did not know right from wrong or did not understand the moral nature of the act because of a mental disease or defect. This is often called the M’Naughten rule, from a case that dates back to a British High Court decision of the eighteenth century.

The other test is often called the “irresistable impulse” or the “policeman at the elbow” test. Under this standard, if the urge to commit a criminal act was irresistible due to mental disease or defect regardless of whether the actor knew right from wrong, the actor is legally insane. The shorthand expression for this is, “Would the guy have done this act even if there were a policeman standing right next to him?”

Finally, there is the more general “Durham Rule”, so named after the standard announced in Durham v. US. Basically, this requires simply that the defendant’s criminal act must be the product of a mental disease or defect; its influence is seen both in the M’Naughten Rule and the irresistable impulse rule.

Finally, I would note that there’s a big difference between “insane” and “competent to stand trial.” The “insane” standards are those I mention above; the standard for being competent to stand trial is generally being capable of understanding one’s position as a criminal defendant and the nature of the criminal proceedings and able to participate in one’s defense.

I will spare you a symposium on “diminished capacity” at this time. :smiley:

  • Rick

For the record, I’ve often seen a third catagory of multiple murderer: a spree killer.

As others have stated, a mass murderer kills a bunch of people in one incident, with most or all of the killings taking place at one location. The Columbine killings and the southern california (don’t remember the city) McDonalds killings were examples of mass murders.

A serial killer kills a series of people over the course of months or years. There is a cool down period between murders, sometimes a lengthy one. Most often these murders are a result of some sort of sexual impulse. Think Ted Bundy and Jack the Ripper, here.

Spree killers kill a number of people over the course of several days, or even weeks. However, unlike with serial killers, there is no cool down period between murders. Unlike a mass murderer this type of killer takes his (or her) show on the road. The murders are scattered in location, but are all part of a single expended incident or spree. I don’t have access to my library, so Charles Starkweather is the only example of this type of murderer that I can think of off the top of my head.

Jess (who is once again frightened at evidence of the type of thing she keeps in the top of her head!)

I believe the sexual serial killer is a unique class unto its own. As I recall, they share a number of unique traits and a similar “profile.” Bundy, Lucas, and Dahmer fit the profile closely, but I’m going from memory here, so take it with a grain of salt:

*White male, aged 17-34

*Repeatedly sexually abused as a child, usually by a close relative

*At least one extremely dominating parental-type figure during childhood

*Drawn to animal torture, with a form of “escalation” from small creatures to larger ones over time

*Not unrelated, several sexual serial killers had favorite pets killed by a parent/guardian as children

*Usually test above average on standard intelligence tests

*Tend to keep “trophies”–mementos of their victims. Also tend to collect newspaper articles about their crimes.

*Preferential to red vehicles, particularly vans or capped pickup trucks, with an overall preference to Volkswagens.

That last bit may seem a bit odd, but the VW microbus was perfect for transporting the cargo that serial killers have a nasty habit of acquiring. Bundy drove a Beetle. Nowdays, serial killers probably use something else. Why red? Well…

And naturally, every individual sexual serial killer has exceptions to these guidelines. One notable case was that Rochester killer who originally escaped detection because it was felt he was too old. When he was caught it was theorized that his long stint in prison had kept him in a sort of emotional stasis, and resumed his habits upon his release as if he were a younger man.

Just to add a few things to Sofa King’s post:

The profile he described was developed by the FBI under profiler John Douglas, author of several grusome books on the subject. It’s suprising how close to this profile many sexual predators turn out to be. Unfortunately, the profile was so reliable that it occasionally led investigators to overlook that 30% or 40% that don’t fit the profile exactly.

Another conclusion of Douglas’s is that almost all serial killers are sexually motivated in some way. So sexual killers aren’t really a unique class, they are the class.

As for spree killers, the most recent example is Andrew Cunanan(sp?) the guy who capped off his cross country killing spree with the murder of fashion designer Versaci(sp?).

One of the rare exceptions to this is the case of Eileen Wuornos, a white prostitute from Florida convicted of (and executed for?) killing several of her johns.

Also, don’t forget Wayne Williams (a black man), convicted for the Atlanta child murders that took place in the late 70’s/early 80’s.

Taken with a grain of salt but here’s some additional info anyway:

43% were sexually molested
42% were physically abused
74% subjected to ongoing psychological torture

Also, as was pointed out before, the tendency to abuse animals. This behavior is part of what is called the Triad (three childhood symptoms that criminologists regard as major danger signals). The other two are prolonged bedwetting (more than 60% of serail killers were stil wetting their beds as adolescents) and juvenile pyromania.

(This info from The A-Z Encyclopedia of Serail Killers)


I have a hobby. I have the world’s largest collection of seashells. I keep it scattered on beaches all over the world. Maybe you’ve seen some of it.

Wayne Williams was convicted of two murders, neither of them children. He has not been linked to any other of the murders lumped together as the “Atlanta child murders,” but the Atlanta PD closed the cases anyway.

According to the book The Evil That Men Do: FBI Profiler Roy Hazelwood’s Journey Into the Minds of Sexual Predators, the term “serial killer” was coined by FBI agent Bob Ressler in the early 80s. Prior to that coinage they were referred to as “multiple murderers.” Hazelwood broke them down into types: organized; disorganized; mixed.

Organized: “Indifferent to his fellow humans, irresponsible and self-centered - the classic psychopath. he is manipulative, deliberate and full of guile, outwardly amiable as long as it suits his purposes.” Tend to prey on strangers.

Disorganized: “He has few, if any, social skills. Typically he is a loner and manifestly so. He may not wash or shave for days, or change his clothing or comb his hair. he feels rejected, and for the most part is incapable of forming normal relationships with other people of either sex. He…commits his crimes on impulse, in a frenzy, with little planning or preparation.” May prey on friends, relatives, acquaintances, indifferent during the act to the threat of capture. Tend to score lower on standardized tests than organized offenders, but have high “animal cunning.”

Mixed: Can either tend to be organized with bursts of disorganization, or vice versa. Think Unabomber and Ted Bundy.