How many active serial killers are in the US?

Ever since Dexter made serial killers lovable, America has had a thing about serial killers. Who are we kidding … America has always had a thing about serial killers. We're fascinated by them. We gobble up true crime books like Thanksgiving turkey. We cast sexy young thangs to play them on television and in movies. We soak up the spectacle whenever one of them is finally brought to justice. And late at night when we hear an unexpected creak somewhere in the house, or rustling in the bushes, we kind of worry for a moment that one of those serial killers might be coming for us.

But should we? According to Scientific American, there are 25 to 50 serial killers operating in the US during any given year, and they're responsible for maybe 150 murders annually. But wait, can't we get numbers that are a little more specific than that? Not really. It's not like serial killers go around wearing t-shirts that say "Kiss me, I'm a serial killer" or anything. Serial killers don't have to be obvious about what they're doing. They hide bodies. They cover their tracks. That sometimes makes it difficult for police to even know someone has been killed, let alone be able to connect two crimes to the same killer.

One hundred fifty murders seems like a lot, but in the grand scheme of murders in the United States, it's a pretty tiny percentage of the 15,000 murders that are committed every year. So the oversaturation in the media gives us this sort of bloated perception about how bad the problem really is, when in fact serial murder just doesn't happen that often.

Interestingly, it isn't just the number of serial killers we've formed false ideas about, it's the sorts of people who commit serial murder, too. Contrary to popular belief and Dexter, serial killers aren't always white males. Women actually commit something like 17 percent of all serial homicides in the United States. And there are plenty of cases of non-white serial murderers, too, in fact by some estimates up to 20 percent of serial killers are African-American. 

The most terrifying thing we think we know about serial killers but don't, though, is this: Serial killers are usually not reclusive, weird loners. They are normal-appearing people with jobs and families. That's one of the reasons why police have such a hard time catching them — because they don't stand out. So serial murderers may be rare, but if one does show up in your neighborhood, you might have a tough time spotting him. Or her. Sleep well.