Friday, May 2, 2008

Crime investigation using fingerprints in Montgomery County Texas

Do you know we have a new machine at the county jail to take fingerprints? Our county took a big leap this year to improve response time on identifying criminals wanted elsewhere and building a database of local criminals. In the Sheriff's department, there is a full time employee just for taking prints and acquiring data on each person brought in. Why would we emphasize one technique of criminal investigation so strongly?

To start, are identical twins identical in every way? Genetically they are. Are there any two people in this world with the same fingerprint? Not to any one's knowledge. So you see, identical twins do not have the same fingerprints. The reason is that the development of the ridges, swirls and circles in a fingerprint are affected by environmental factors, not genetics. This applies to foot impressions, hand impressions AND fingerprints. The right hand is also different from the left. This is due to pressure points and the position the fetus when laying in the womb. The print can even be influenced by factors outside of the womb during the fetal development. The science of finger printing is amazing these days. Yet it remains tedious and time consuming. Therefore, we have more than one expert on our county's criminal investigation staff to work with fingerprints.

I had the good fortune to see the equipment and meet the operator in the county jail, and meet a CSI (Crime Scene Investigator) in a seminar recently. Caryn is one of seven CSIs who might be assigned to a case here in The Woodlands. In 2007, 2200 fingerprint enquiries were run through the AFIS state database, 13000 palm prints taken and 31000 fingerprint cards created.

Fingerprints are very important in a criminal identification. It is the quickest way to positively identify a person. There are at least five formal classes a CSI should take to become an expert in the field. Fingerprints can be taken from a straw, piece of paper, a sugar envelope in a restaurant, inside a latex glove, and extracted from many other places we would not think would be possible. Very strong evidence is often the result of acquiring reasonably good fingerprints. Can one alter or mask his fingerprint so he cannot be identified? Yes, but the techniques used will be evident on the body or fingers of the individual that the prints have been altered.

I laughed when Caryn told us that when she sees a Giraffe or a Zebra, she immediately thinks of fingerprints. Every Zebra's striped body is different, and so the analogy. Must be tough to have this profession. I prefer to see a beautiful Giraffe instead of a bunch of unique lines.

You want to know a little more, like the anatomy of a fingerprint? I can give you a fundamental technical principal. A print has three basic elements. (1) Loops - concentric U shaped lines. Think of the end of a string starting in position A and laying it in one direction then bending it at some location C and returning the other end to a parallel location with A, call that B. Now you have sort of a triangle. You looped the string. (2) Whirls - oval closed shaped concentric lines. Take a piece of string and make a circle by placing both ends on top of each other. (3) Arches - lines that intersect each other but do not return to the beginning. Take a string and just place it in a straight of curved line that looks like a highway and you have one arch.

What makes the process difficult and time consuming is that a CSI must identify at least 20 places on each print and put them into the database. For example two ridges intersecting at an (x,y) location. These 20 points help the database respond to queries finding potential matches of a fingerprint. The eyes continue to be the best analyzer tool for determining if there is a real match or not.

Over many decades of refining the process and developing tools to make the process effective, today we have a sophisticated "fast" identification capability, yet unlike the CSI show on TV, it still takes hours or even days to come up with a positive ID if that happens at all. It is just one tool for a CSI to help unravel the crime scene and provide sufficient data to detectives to find the suspect(s) or to the court for a verdict.

Another aspect not to be overlooked! Our children and ourselves should be fingerprinted. If we get passports or are immigrants, we have already been fingerprinted and the print is in the national AFIS database. If not, we can take fingerprints ourselves and store them in a safety deposit box just in case one of them disappears sometime. Just use a stamp pad and ink the prints. Use a photo of the person and print on the backside. The prints are good forever.

Another significant aspect to not be overlooked! Do you know that all county employees are finger printed? More significant than that is every single licensed tow truck driver is finger printed and has a special colored identification card. That means every deputy who might want you to get in a car must have proper photo identification and every tow truck driver who may have you accompany him must have a photo ID badge. All licensed attorneys also have such a badge. A tow truck driver must have a PINK ID badge. The color is very significant. He must also have a green sticker on his windshield in order to operate in Montgomery County. This is very important to know! Do not get in a car without the driver having the proper photo identification. ASK FOR IT! DEMAND IT!

Montgomery County has a strong Crime Scene investigation staff with excellent credentials. Hopefully we will not ever need one to be working on a case in our neighborhood or in our own family. But if we do, there are some very fine folks in Conroe able to help solve the crime, fingerprints just being one but significant tool to do so.

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