Slashdot Mirror
Geoprofiling Moves Into The Limelight
circletimessquare writes "Interesting and timely. A short piece at CNN talks about the software helping to track down the sniper currently terrorizing the Washington DC area. It was the doctoral thesis of a cop, Kim Rossmo, who developed it while walking the beat in Vancouver and reading about the hunting patterns of African lions. Googling, I found an older but deeper piece which mentions more of the tech behind the software, called Rigel. That led me to the website of ECRI, the company that makes Rigel. More good tech there."
Subsonic bullets would negate the entire reason for the .223, namely the extra powder charge. The point of the rifle bullet is to fly very fast. Most likely they didn't hear loud shots because the urban environment is actually very noisy.
If the shooter was a fair (300 yards+) distance away, the sound would be less, due to the distance. As well, I would imagine the clutter associated with an urban area would play havoc with the echo. As well, the bullet would arrive before the gunshot sound unless it was a subsonic round, which I have never seen, and agree that they must be more difficult to find, especially in the caliber the shooter is using, .223, a round that relies on high velocity to be effective.
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
It is possible to put a suppressor on a .223 rifle. This would make it much harder to identify, by sound, from where the shot originated. BTW, you don't have to "find" subsonic .223 rounds, you can just reload.
Note: I work at ECRI, but I'm not speaking for my employer. I will answer basic questions in the comments here, though I can't always go into detail.
GEO-PROFILING: POTENT NEW POLICE TECHNIQUE
Cracking the Toughest Serial Criminal Cases
Dec. 31, 1998
By Jim Krane
SAN DIEGO (APBnews.com) -- Picture a small city in eastern Canada whose residents were rarely touched by violent crime. Then, startlingly, a serial rapist began attacking women, injecting a dose of fear into a normally tranquil community.
By the time the assailant sexually assaulted his 11th victim, police were desperate. They compiled a list of 300 possible suspects and prepared to conduct expensive, laborious DNA tests on each one, hoping to match DNA residue taken from victims.
Vancouver Police Detective Kim Rossmo
That's when Det. Kim Rossmo got a call.
Rossmo, a detective inspector with the Vancouver Police Department, developed an investigative technique called geographic profiling. Using geo-profiling, police try to trace a serial criminal to his home or workplace by computing distances with geographic clues he's left -- such as dead bodies, sites of attacks and other known locations the lawbreaker visited.
Rossmo explained geographic profiling to attendees at the International Association of Crime Analysts here recently, giving criminal analysts a window into one of law enforcement's newest and least-known investigative techniques.
Rossmo's methodology would come in handy on the serial rapist case and many others.
Valuable search tool
As part of his doctoral research at British Columbia's Simon Fraser University, Rossmo developed an algorithm -- a mathematical model of repeated calculations -- that targets serial criminals by the spatial patterns they produce.
Since then, Rossmo's algorithm has been computerized, allowing it to make hundreds of thousands of calculations that pinpoint a criminal's hideout within a fraction of the crime site area.
Priority: danger
Rossmo most often gets a call when a serial criminal is on the loose. Since many agencies -- in Canada, the United States and Europe -- seek his services simultaneously, Rossmo said he gauges which community is most at risk.
In the eastern Canadian sexual assault case -- Rossmo didn't want to divulge the location -- his geographic profile turned out to be remarkably accurate. With 300 suspects on their hands, the local police could only look forward to a lengthy period of laboratory testing.
The red peaks in this image identify the probable location of an offender's residence in Vancouver, British Columbia.
But Rossmo's geo-profiling technique helped the police get their man much more quickly. The Vancouver detective visited crime scenes, read reports, and talked to victims and investigators. He analyzed the data using his computerized algorithm and found a neighborhood hot spot to focus on.
Seventh time's a charm
Instead of hauling suspects in alphabetically by last name, police matched suspects' addresses against Rossmo's findings and tested those who lived nearest the hot spot's peak. The seventh suspect lawmen tested was a positive DNA match. Police arrested the man and cracked the case.
"If they didn't have geographic profile prioritization, they might've started with Archer and ended with Young," Rossmo said.
Lazy to a fault
Despite its complicated mathematical calculations, geographic profiling is based on a simple theory. Criminologists say most humans -- criminals included -- are inherently lazy. Just as a person will shop in the grocery store nearest his or her home, a predatory criminal usually picks his victims in familiar areas -- except for a small buffer zone around his home, says Rossmo.
Thus, when an arsonist sets a series of fires, police can estimate his whereabouts (usually a residence) by dumping the addresses of buildings burned into the computer and calculating the location most central to the crime scenes.
Crime as topography
In reality, Rossmo's crime-busting technique is more complex. He walks through crime scenes, conducts interviews and reads police reports. With years of investigative experience under his belt, Rossmo puts emphasis on certain locations based on his psychological assumptions about the quarry. At the same time, he discards or discounts other locations that he believes might skew his findings.
Rossmo then keys his data into the computer. The machine converts street addresses into latitudinal and longitudinal coordinates and creates a three-dimensional "jeopardy surface" or topographical model of the data. The jeopardy surface looks like a mountain range, with colored bands of peaks and valleys that show where the addresses converge -- the peaks -- and where they don't -- the valleys.
When Rossmo superimposes the jeopardy surface onto a street grid, the result isn't an exact map to the killer's house, but it's something close to it.
Method used in 80 cases
Since 1990, Rossmo has used his geo-profiling technique in more than 80 cases, representing 1,800 crime locations. He believes his work helped crack about half of those cases.
But Rossmo doesn't measure his success only by cases cleared. He's interested in geographic accuracy.
In cases where an arrest has been made, Rossmo's been able to estimate the location of the offender's home within the top five percent of the search area. That means, if police believe the offender lives somewhere within a 10-square-mile area, Rossmo can tell investigators which half-square-mile section to search.
In some cases, he's more accurate. In the Canadian rapist investigation described above, Rossmo's suspect lived within the first 2.2 percent of the area searched.
The more a criminal strikes, the more clues Rossmo can enter into his computer. Theoretically, that makes his predictions more accurate. But Rossmo's computer doesn't spit out a name and address. After the computer does its thing, Rossmo writes a report suggesting strategies for capture.
"It's the investigator that solves the case. Our role is to support him or her," Rossmo said.
Cops, meet Rigel
Rossmo's algorithm has been incorporated into a software program called Rigel, manufactured by the Vancouver firm Environmental Criminology Research Inc. (ECRI). Rossmo is a member of ECRI's board of directors and acts as the company's chief scientist.
Currently, Rigel runs only on a Sun Microsystems UltraSparc workstation. But ECRI is reprogramming it for use on Windows NT workstations and servers.
The software isn't cheap -- ECRI president Barry Dalziel priced a copy at $70,000, which includes some training and help with installation.
Rigel, emphasized Dalziel, isn't perfect. For best results, it should be used by a police investigator or crime analyst who undergoes a year of training, some of it under Rossmo's personal tutelage.
"If it sends them off on a wild goose chase, police investigators aren't likely to use the system again," said Dalziel.
It's a Canadian thing
Besides Rossmo's Vancouver Police, two other agencies have been trained in geographic profiling with Rigel: The Royal Canadian Mounted Police, Canada's national police force, and the Ontario Provincial Police. Rossmo said the British National Crime Faculty, another national law enforcement agency, will be certified in 1999.
No U.S. law enforcement agencies are on Rossmo's training list -- even though he's been invited to help crack dozens of cases in the States.
The real Robocop
If its geo-profiling uses weren't enough, Dalziel said investigators will be able to use a new version of Rigel to predict a serial criminal's next crimes, including dates and crime locations.
And cops will be able to predict and monitor the likely "hunting grounds" of paroled sex offenders by plotting past crime data and behavioral traits into Rigel, said Dalziel.
"Say there were crimes in that area that matched [a parolee's] M.O., his name would pop up," Dalziel said.
Jim Krane is APB News staff writer (jimk@apbnews.com).
I wear pants.
M-14's not .223, it's 7.62 NATO (.308 Winchester). I think you may be thinking of M-16, which does fire 5.56 NATO. The Mini-14 (which you also might have confused the M-14 with) is also a .223 rifle, but not nearly as accurate as a sniper would need. I'd vote for some variant of Remington 700, for accuracy's sake. However, an accurized AR-pattern rifle might well do the job. Were this sniper using an M-14, there'd likely not be the survivor that there is - the 7.62 round is much more lethal.
There is no such thing as a subsonic .223 round, but not because of the reason you gave. The long .223 case means that if you lessen the charge any (which is what is done to produce subsonic ammo) then the powder can move around in the case, thus causing problems iwth ignition and firing. There is a solution, which uses a necked down .338 case which is shorter, but that's further offtopic. Also, making a subsonic .223 round does NOT negate its purpose, as then you have a subsonic projectile that still has good armor piercing ballistics (as opposed to a subsonic 9mm or .45 round, which would literally bounce off body armor)
If you can't see the value in jet powered ants you should turn in your nerd card. - Dunbal (464142)
No, I think he's just got a lot of "stuff" around him (grass, bushes, etc) and is pretty far off. Cities are loud places, much more so than out in the woods. You'd be very surprised how quiet even a big hunting rifle is from a couple hundred yards off. And sound can echo off things fairly effectively in a city (although I've never shot a gun in a city, I've shot quite a few of them in the country, so I'm partially guessing here). If the victim was hit a second or two before the shot was heard, that confuses things even more. You'd pretty much have to see the impact to know where it came from.
Whatever he's using, I can't think of a fate bad enough for this guy. There's a special place in Hell for those who shoot women and children in the back. I just hope he's found soon.
-B
Ash and Hickory, straight-grained and true, make excellent bludgeons, dandy for the cudgeling of vegetarians.
This technique was demonstrated in "Badge of Deceit" - The Randy Comeaux Case, a "Forensic Files" episode on CourtTV.
Kim Rossmo got his Ph.D. in criminology at SFU. The ideas in his thesis weren't just sudden inspiration -- they came from his many years as a police detective working on investigations, and from rigorous academic study and research.
How does this work? Alittle bit about geographic profiling works. Essentially, what this software does is it assigns a weight to different attributes of a crime and based upon past crimes determines a probability that the crime was commited near someone's home or an area they know. Throwing in some additional variables such as where an individual works, what route they probably take to work, etc, helps identify a person's individual daily path. Throw in a couple more factors like how far most criminals go from home to comit a crime - i.e. bank robberies tend to happen at banks individuals don't know, further from home, though rapes and murders happen in areas people are more comfortable - near an area they know - so that if discovered they know where to run (read: no unexpected dead end roads, good alleyways etc). Without getting into the whole theory of why this is - basically its because someone near their home doesn't stand out, they've probably been seen on the street before, maybe a neighbor knows them, they dont pose a threat - and dont' look out of place. Think about yourself - if you had to go walking around alleyways to stake out a location to dump a body or commit a rape, would you feel more comfortable (and look less shady) in an area you know, or some place out of town? So take some basic variables - what was the crime? when was the crime? Now, take the location of your crimes and cross-reference it with just the areas that would match given crimes. You end up with an area of probability that usually circular in nature around each crime... as these areas intersect, you get "blotches" of red, yellow, orange, etc.. That done, start to take other factors into consideration. You probably don't have a database with everyone's job, route to work, schedule, etc - what you probably do have is income ranges and general demographic information for specific areas. (Ok so I mentioned all this stuff about individuals above, I'm getting there). Using that data, you can modify the predictions futher. For example, something like a string of gang shootings... There are several areas (chicago for one, im sure you can think of one near you) that have affluent or up-and-coming areas near or next to ghettos. For chicagoans, think near west side vs. cabrini greens. For those who don't know, 2 bd 2ba condos in near west side go for about $300,000 to $500,000. Go about five or six blocks down the road though and you'll run into section-8 housing. I'm getting to a point here, bear with me. Having run your first analysis, you may find that there was a gang shooting in the "nicer" area, but it isn't really likely the shooter is from there... more likely than not, he's from the crummier side a few blocks away. Up to this point, the system knows nothing about Street Y vs Street X. Street Y might be a few blocks from Street X, but STreet Y might be primarily a six figure area... This information exists - if not directly, it can be found through housing prices and general crime level. Ok, so now what? We have a big red blob that winds around. Feed the system the data on population type, ethnicity (yup. Not too PC, but its there), income, average age... etc. With this new info, it starts to eliminate or decrease the red areas, building a smaller search section. Now I'd talked about all those individual factors - I'm finally getting to them. Remember those? Where does person A work? Person B? What does this person do? (Truckers and transients dump bodies far away, most employeed people dump them near work or home) .... etc.
Usually in cases like these you have hundreds of leads. Everyone is followed up - some are easy to eliminate some don't really lead anywhere. Some sound like good potentials. Say you get a tip that joe shmoe did this crime. A quick check reveals he has no alibi for the time in question... does he fit the (geographic) profile?
Obviously, you are going to go see joe shmoe. You ask some pretty basic questions that sound pretty boring... where do you work? You drive to work? Take the bus? What time do you leave? Do you eat lunch at work or outside? Simple stuff. You bring it up in conversation like nothing was - and for the most part it isn't anything.
Pretty soon, you've got a list of 50 individuals who could all be involved. None of them have alibis, and you need to figure out who to focus on. Here we go again.
Your now narrowed red area can take into account what these people do, where they work, how do they get to work, etc. Put those in and usually, you end up with 10 individuals who fit the geographic pattern. Those are the ones you go see again. And again.
The rest? They don't fall off the radar, but you are no longer dedicating half your team to them. It's a game of probabilities. Now with your 10 "likelies", you've got the resources pointed in the right direction.
Combine this with an FBI Profile of an individual and you've taken your 10 and shaved off 3 or 4. Now, you've got a handful of people to really focus on. At this point, you've got your search warrant if you want it - no alibi, meets the profile, fits the area, etc.
The search warrants usually lead to a few more clues and narrow it down to one guy. Then you just got to figure out how to prove it was him. :)
(reposted since I did it as anon by accident)
having witnessed a Gem-tech supressor on a .223 at the defcon shoot ( http://www.23.org/dcshoot/ ) if you have an effecttive suppressor you really dont need subsonic rounds.
all you will hear is a "zip" or a "crack" type sound (depending on how close you are and what angle) from the supersonic shockwave. unless you have heard it before you probably wont pick it out in the middle of a noisy street.
That is a good point, This guy hits reliably and doesn't freak out. My own take is that this is someone with military sniper training. What bothers me most about that is that sniping is hardly glamour killing; its boring, monotonous work. I have a very hard time understanding why someone who is killing people for some sick kind of emotional reward would do it this way. It is, however, probably the best way to get away with it. Then again, I worry about anybody who could get inside this guys head. He is very scary.
-- Rich
Free your mind and your Ass will follow -- George Clinton
But, of course, ANY round you think of probably exists on some wildcatter's bench somewhere, as well as a gun to make to do something you wouldn't expect. Many
However, since the whole concept of the 5.56mm as a military round (as compared to
Noteable also that a 9mm or
Some of the things you said just aren't true. As an experienced handloader and target shooter, let me help you out: Subsonic .223 rounds (which is really to say, a loading that propels a .224 [22 cal] projectile) do exist for ANY common weight of 22 caliber bullet, from 40 grains to 70 grains. My friend who has a Thompson Contender in .223 makes such loads for shooting on an indoor pistol range where supersonic loads are forbidden. The problem is to find a stable loading for the rate of twist of the barrel, mass and shape of bullet, and other factors.
Many, many loadings don't fill the brass all the way up. The primer will cause all powder to detonate whether next to the primer or at the other end of the case, there's plenty of time for that until the bullet leaves the weapon (pressure should build uniformly until that happens). Using a fast burning powder, you may have mostly space in the cartridge, while a slower one may fill it just about all the way up.
I don't know where you read that. A witness near the school shooting heard a loud pow, and some people inside a restaurant heard the gunshot near a gas station tonight (if that was the sniper), and several other witnesses reported hearing loud bangs in other attacks. (The Washington Post website has been down for the last couple hours, or I'd find a source or two.)
He may be wearing a cloak of invisibility, but his rifle isn't silent.
Vancouver's Mayor had more police manpower directed towards a high profile pot shop in the area than the case of the 50 missing women. Rossmo's thesis was pooh-poohed and he was demoted and effectively run off the force.
The missing prostitute case continued to be a willfully low priority of the Vancouver police department until it recieved some publicy (including, I believe, being featured on "America's Most wanted" -- "Vancouver's a great place to be a serial killer -- cops cry '50 missing and all's well!'"
A little over 2 years later, they've charged a guy with killing 15 of those missing women, and are searching for more remains on his pig farm.
From what I've been able to piece together, he abused them, killed them, ran their bodies through a meat grinder (or branch grinder) and buried the ground-up bits on his farm.
In the meantime, Downtown Eastside residents who were formerly unwilling to report mysterious disappearances of friends to the cops have now brought the number of missing women into the 60 person range.
More info on the missing women case can be found on the CBC website.
Free Software: Like love, it grows best when given away.
This individual does not have military training as his shots have actually not been that accurate and he is not killing for the sake of killing ... so he is doing the killings with a commonly available shorter barrel AR-15 derivatives
If this guy is making long shots (500 yds +) with an AR-15, then he is as accurate as the most accurate military shooters (I am assuming no scope here). I know, I was a rifle coach/sniper in the USMC. The bullseye used at 500 yds by the USMC represents a man's head and chest. And not even the best shots hit it every time. To get better than that you have to use scopes and bipods, as well as weapons that are tighter than the standard issue M-16. By the way, I am assuming that this guy is making long shots because of the varying reports as to the sound of the shot.
-- Rich
Free your mind and your Ass will follow -- George Clinton