Scene of the Crime

by Anne Wingate

  You've started by dusting the door frame, just in case somebody you didn't know about was in the house that night. Now let's see how the lift is going to look, in Figure 4-3.

  Who initials those cards? Why, you, of course-Detective N.E. Boddy, and your partner, Mel(vin) or Mel(anie) Smith.

  That's about the best you're going to be able to do on this surface; too many hands have been laid on top of hands for you to get anything more identifiable than a bowl of spaghetti. It's time to start on those seventeen liquor and wine bottles. If you just had one you might take it in and dust it in the office, but with seventeen, there's too much chance of bottles rolling against each other and breaking, or of prints being rubbed off by paper rubbing against the bottles. So you're going to do it all right now, right here.

  Bottles can be tricky. The surface is so glossy that regular fingerprint brushes, even carefully used, tend to cut the print. You have something special to use on them: magnetic powder, so nothing except the powder itself will ever touch the surface being dusted. The "brush" is a wand containing a magnetic metal post inside a flexible closed rubber tube, and the fingerprint powder is extremely finely ground black iron filings. The wand can be held in either of two positions: with the metal post held up in the handle, so that the tube does not pick up fingerprint powder, or with the metal post pushed down into the tube, so that the tube does pick up the fingerprint powder. Theoretically, magnetic powder cannot be used on any surface that reacts to magnetism. But that, as you'll see later, is only theoretical.

  All right, you've made several lifts from this bottle. You already know what the fingerprint lifting card looks like, so let's not bother with making more of them. Instead, let's go on and write up the evidence tag (see Figure 4-4), as you're going to want to take all the bottles that held prints into the police station with you.

  Notice that once again, both you and Mel initialed the card, although only one of you collected the evidence. Notice also that each individual piece of evidence collected at any given crime scene will be given a separate item number, keyed to notes in the investigator's notebook. How many items might you collect at a crime scene? As few as zero, as many as thousands. How long does it take? It takes as long as it takes. There's no other possible answer. I spent two entire days working a crime scene inside an automobile, collecting several hundred pieces of evidence. As I recall, in the real Jackson Street Corpse case, I spent several hours there that afternoon.

  It was a Saturday. I had been shopping, and I did not possess a pager. Police cars all over town were asked to look for me, and an

  officer spotted my car in the parking lot of a local department store and went in to haul me away from a going-out-of-business sale. I had my younger daughter, then not quite a year old, with me; she still remembers waiting in the car (a police officer played with her while I worked the crime scene) and then being dropped off at the day-care center long enough for me to wash my hair in the darkroom.

  I went back again for several hours on Sunday and again on Monday, before I was to the point I could call myself through at the scene. How well I yet remember—I had ident all to myself then; it was before we had added a third person. Doc went on vacation to Florida, and the last thing he said to me before he left was, "I hope you have a corpse a day while I'm gone." He meant it as a joke; we'd never had that many in that short a period. (Doc's vacation lasted thirteen days. I had nine corpses, starting out Friday at 4:30 p.m. with a triple shotgunning where several innocent bystanders got in the way of a drug deal that went sour.)

  But the murder rate increased steadily. The first year I was with the Albany Police Department, we had four murders the entire year. The last year I was there, we had four murders before New Year's Day was over.

  Mere About Collecting Latents

  Let's move on now to some more general methods of collecting latent prints, and look at a few more specific examples of those methods in use. Bear in mind that we're still talking about collecting latents; we'll get on to fingerprinting people (alive or dead) a little later.

  There are four main ways of collecting latents:

  • Dusting

  • Spraying

  • Dipping

  • Fuming.

  Dusting is the most common. You've already looked at dusting with a regular brush and with magnetic powder. In general, magnetic powder is never used on magnetic objects; that is, it is not used on steel, iron, or any other object that has any built-in magnetic property of its own. But that generalization, like most generalizations, is not true in some specific cases. And therein lies a tale. I remember it well. So does the Georgia Supreme Court, to which it was appealed.

  How ihe Georgia Supreme Court Ruled Me Expert

  A small mom-and-pop grocery store was robbed. I was busy on something else; I didn't get the original call. Detective Howard Yelverton got there soon after the uniform officers did, and because the perp had definitely fled on foot, Howard called for the dogs.

  Bear in mind that you must use specially trained dogs to find a scent trail, although bloodhounds are not required. In Albany, Georgia, when we needed dogs we borrowed them from the nearby Lee County Prison Branch. The dogs—actually one dog, a well-trained German shepherd —arrived in a truck. His trainer showed him where the trail had started, and he took off through yards and back alleys. A couple of blocks away, he stopped at a house and began barking lustily—nowhere near a door. In fact, he was standing by a back wall jumping up and down and barking.

  The trainer took a look and called Howard, who was following a few paces behind the dog. Howard took a look, reached for his hand radio, and called me.

  By the time I arrived, the dogs were gone. But the television cameras were still there, and the television news later showed a picture I could really have done without: me from the back, leaning over, very carefully collecting the shiny bright chrome-plated .38 revolver that the perp—whoever he was—had stopped long enough to drop behind a loose board.

  The people in the store said their assailant had been very careful about prints; he'd wiped with his shirttail everything he touched. Evidently he did that with the revolver, too. He very, very carefully wiped off, with his shirttail, every fingerprint he'd left on the revolver until that moment—and then, equally carefully, he took the revolver in his hand, leaned over, and placed it inside the wall behind the loose board—leaving behind probably the best thumbprint I had ever seen in my life. Because of the angle of the sun, Howard saw the print as soon as he saw the gun.

  As the detective and the television news team went on after dogs and dog trainer who were on the perp's trail, I rushed into the police station. I had a bit of a problem. Although the print was visible, and gorgeous, I had to get powder on it and lift it before I could begin to search it—that is, to find out whose print it was. And chrome is an extremely hard and glossy surface; powder and brushes, even the finest powder (which isn't fingerprint powder at all, but powdered photocopier toner) and the softest brushes tend to cut prints on chrome.

  I had a good print on one side of the revolver. Turning to the other side, I made several test prints of my own thumb and then methodically began to try out different powders and brushes. Lo and behold, the mag powder—which is supposed to be unusable on any magnetic surface—worked beautifully on the chrome-plated steel. Turning the revolver over, I dusted and lifted the print. Then I headed for that collection of 10,000 fingerprint cards and started searching.

  I knew that I had a thumb. I knew which hand it was from. I knew the pattern on that thumb. That narrowed the search down to less than 2,000 cards. But just for the heck of it, before I started searching the whole file, I searched the cards that were already on my desk.

  And there it was. He'd been arrested for public intoxication less than two weeks before, and I still hadn't finished classifying and filing his card.

  By the time dogs and police hauled Leon McCoy out of the house he had holed up in, I had his fingerprint card out with the latent li
ft paperclipped to it.

  Yes, this time I'm using the perp's real name. After the kind of publicity that one got, there wouldn't be much sense in trying to disguise it.

  Why the appeal?

  The first trial was declared a mistrial. For the second trial, nobody could find the fingerprints and charts. The court thought I had them, and I thought the court had them. (They turned up, years later, in somebody else's file. To this day nobody knows how they got there.) Leon McCoy said: (1) I wasn't a fingerprint expert; (2) it was improper to base a conviction on fingerprints nobody could find; and (3) we were persecuting him because he was a Muslim.

  The court ruled: (1) I was a fingerprint expert; (2) although normally the prints had to be produced, this was an unusual situation and the prints had been seen by enough people that the court decided their discussion, without their production, was proper; and (3) nobody but Leon McCoy seemed to care that Leon McCoy was a Muslim. (In fact, the local imam had in effect disowned him, and it was perfectly obvious why. Proper Muslims do not become intoxicated, in or out of a public place, nor do they go about robbing stores and then trying to get away with the crime on the basis of religion. Islam was at that time working very hard to be accepted in Georgia as a proper religion, and Leon McCoy wasn't helping much.)

  I will add that of all the criminals who, after conviction, have ever promised to "git" me, Leon McCoy is about the only one I think is crazy enough to try. But it was still an interesting case. If you want to read more about it, it's Leon McCoy v. The State of Georgia. My name then was Martha G. Webb. (Never mind how I turned into Anne Wingate. That's another story entirely.)

  Finding Latents en Paper

  In general, paper is fumed or sprayed. But highly glazed paper, such as that found in high-quality magazines, is best treated by powders. In one case, the home of an FBI agent was burglarized. On the back of the FBI magazine found on the agent's nightstand was an enlarged photograph of an extremely interesting fingerprint — and fingerprint technicians dusting the glazed magazine cover found the fingerprint of the burglar on the photograph of the fingerprint.

  Spraying is probably the second most common means of testing for latents; on paper, it is the most common. A chemical called ninhydrin is the most widely used spray; its chemical name is triketo-hydrindine hydrate. Ninhydrin, available commercially in an acetone solution, has an extremely strong and unpleasant metallic odor; many technicians also dissolve it in amyl acetate—which gives it the smell of slightly overripe bananas—because some inks run, and some fabrics dissolve, in an acetone solution. However, the acetone is much safer; too much amyl acetate causes severe headaches ... and herein lies a story.

  How not to develop prints on paper and cardboard: The Albany ident section eventually grew to three people. The third was Robert "Butch" Windham. Although he'd entered the police department about the same time I did, he was far less experienced with fingerprints, and he was noticeably hardheaded. When we began using ninhydrin dissolved in amyl acetate, we all knew of its headache-causing properties, and Doc warned us that if we were going to spray more than one or two items we should take them out in the open air to spray.

  One evening, on duty by himself, Butch decided to spray a large number of cardboard boxes. He took them out in the open air, all right—directly under the intake for the police department's air-con-ditioning system. By the time he got through, the building had been evacuated and the entire on-duty dispatch section was in the hospital. One dispatcher, who was several months pregnant, never did return to work. She was not harmed, but she was extremely frightened.

  How to develop prints on paper and cardboard: Although ninhydrin was developed in the nineteenth century as a specific reagent for amino acids, it was not applied to fingerprinting until 1954. Before that, iodine fuming and silver nitrate solutions were used to develop prints on paper. But iodine fumes are difficult to work with and extremely caustic, and silver nitrate, if not carefully controlled, will blacken the entire document.

  When all three are to be applied, they must be used in this order:

  • Iodine fuming

  • Ninhydrin

  • Silver nitrate (which may be sprayed or put in a dish for the document to be dipped in it).

  However, most police departments use only ninhydrin. I have very rarely used iodine and never have used silver nitrate.

  But iodine is essential in some espionage and other cases in which a document must be examined for fingerprints and then sent to its intended recipient, because almost always, iodine prints can be photographed and then treated with ammonia vapor so that they will completely fade out; in fact, they may fade out in the air unless they are sprayed with a fixative solution. Ninhydrin and silver nitrate are generally permanent, although manufacturers recommend fixing them also. (Both tend to be permanent on hands as well as on documents. Fingerprint examiners sometimes have very odd-looking hands. I suspect our lungs are pretty odd-looking as well; a fingerprint technician has to be totally away from work for more than two weeks before s/he quits sneezing fingerprint powder.)

  Ninhydrin, as I mentioned, produces an unpleasant, acrid odor; however, as many as 50 percent or more of all fingerprint cases taken to court now involve fingerprints on paper, and at least 90 percent of those prints are developed with ninhydrin.

  At times our lab resembled a laundry, with dozens of forged checks hung up on several small drying lines. It looked even funnier at the developing stage, when we started blowing the checks with a hair dryer.

  Methods of Iodine Fuming

  Prints developed with iodine are brownish-violet. Iodine fumes must be used inside a container; although commercial fuming tanks are available, an old glass fish tank with a light bulb in it to provide the heat to vaporize the iodine crystals is generally adequate. A sort of blowpipe, in which the technician's breath is blown through a fiberglass filter and over a handful of iodine crystals onto the paper, may be substituted. The paper must be watched carefully, as the prints develop quickly. The prints must then be photographed immediately, as unfixed prints will fade out almost as soon as they are removed from the iodine vapor. (Technicians use a special fingerprint camera, which produces a 1:1 ratio of negative to original — that is, a negative the same size as the original.)

  Iodine works on oils from the skin surfaces that are transferred to the paper. (Fingertips do not produce oils; however, people touch their faces far more frequently than anybody but ident people realize, and oils from the face are transferred to the fingertips and hence to the paper.)

  Methods of Using Ninhydrin

  Ninhydrin is available in aerosol spray cans dissolved in acetone. Large-scale users can obtain it in crystal form; it is soluble in acetone or amyl acetate, and can be sprayed from plastic jars that use plain air rather than aerosol solutions as the propellant. The jars are slightly less efficient than the spray cans, but they are somewhat less expensive and probably safer for the environment. Dipping a document in ninhydrin dissolved in acetone is more efficient than spray cans or bottles, but it is also more likely to cause the ink to run. The spray form of this solution will not cause headaches, but if too much is sprayed in a small unventilated space, the user can wind up with chemical pneumonia. (I know. I did.)

  Dipping a document in ninhydrin dissolved in amyl acetate will not cause the ink to run, and it is more efficient than using sprays, but it is far more likely to cause very severe headaches.

  All of this means that each time ninhydrin is used, the user has to mentally weigh cost, efficiency, the need to keep the ink from running, and the possible health problems. These are all things you can use in fiction, especially if you're writing about a small department or a P.I. with a limited budget.

  The prints developed with ninhydrin—which works on the amino acids contained in all perspiration—range in color from pink to purple. They develop in about twenty-four hours after the paper is sprayed, although some may continue to become visible for up to forty-eight hours after that. Th
e stronger prints develop far more quickly under conditions of heat and moisture; we tried ironing them with a dry iron and with a steam iron, and later switched to the hair dryer, which worked very well.

  However, one time we examined a check for the postal inspector and found no usable prints on it. The inspector then picked it back up from us and mailed it to the Postal Inspection Service Laboratory in Washington, D.C. Somewhere between our office and theirs the prints developed, so that when the check (properly packaged in a plastic sleeve so that no additional prints would be put on it) was removed from the envelope, the prints were quite clear.

  Silver Nitrate in Developing

  Silver nitrate, which reacts with the salt present in perspiration and hence in fingerprints, is used by dipping the paper in a silver nitrate solution or spraying the solution onto the paper. The paper is then exposed to normal light. It must then be watched extremely carefully, as it can go from clear black prints to entirely black paper in seconds. Once the prints have developed, the paper with the solution on it must be stored in absolute darkness, as every exposure to light recommences the darkening. Even paper that has been treated with a fixative will darken, although the darkening will be somewhat slower.

  Other Methods of Fuming for Prints

  Most people incorrectly believe that anything except paper is fingerprinted only with powder. Many other items, such as some plastics and all galvanized metal, are best treated by fuming. But these fumes don't come in a can. When I went through fingerprint school, I was told to burn a magnesium strip, which burns very quickly with a bright white flame and produces white smoke, to fume plastics and galvanized metal. Doc and I tried that exactly once and almost burned down the ident lab. We preferred fat pine (pine kindling wood), which produces a dense black smoke that liberally coats the item held above it. After the item has cooled, the excess smoke is brushed off with a normal fingerprint brush. There is no danger of brushing out these prints: The smoke actually fuses the print to the metal, and it's there forever. Sometimes, in multiple thefts from soft-drink machines, we got the coin boxes back to smoke two or three times and it got hard to tell which were the old prints and which were the new ones.