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LAUNDRY AND DRY-CLEANING MARKS All laundry marks, whether placed on clothing by ships' laundry, civilian laundry or dry cleaner, or an institutional laundry, are designed for one purpose-to identify the owner of the particular item of clothing. In crimes of violence, parts of clothing bearing laundry marks may be torn from the person of the suspect. In some crimes, such as holdups, outer clothing such as uniforms, overalls, or coveralls maybe worn as a disguise and discarded as soon as possible after the crime was committed. Clothing has been found hidden in trash bins and garbage cans, and the suspect has been identified through the tracing of laundry marks. A fugitive may leave his or her dwelling quickly and leave behind old clothing. You may also make use of laundry marks to identify an unknown victim, or to establish ownership of property. Examination Any garment that comes into your possession that requires the identification of its owner should be carefully searched for laundry marks. Take special care during the search if the garment is to be processed for other trace evidence such as hairs, fibers, or soils, to ensure that such evidence is not dislodged and lost. All parts of the garment should be searched so a hidden mark which may have been placed in an unusual location on the garment, is not overlooked. After an initial search, whether it is successful or not, another search should be made with strong cross lighting to discover old, faded markings. An additional search should be made using ultraviolet light to discover markings that may not otherwise be visible. The garment should be sent to a criminal investigation laboratory for further examination, with information indicating any discovered markings and the manner or means used to discover them. This will aid the laboratory examiner in the examination and preclude duplication of effort. By use of light sources of varying wavelength, the laboratory examiner may discover markings that otherwise would remain invisible. Tracing a Mark Be prepared to spend long hours in the time-consuming task of going through the records of the laundry or dry cleaner. Neither ships' laundries nor civilian laundries and dry cleaners have personnel available to search their records. In cases involving ships' laundry marks, it is often advantageous for you to check first the personnel office for a possible identification of the suspect by comparing all names starting with the initial letter of the laundry mark and a comparison of the serial numbers. A check of personnel offices of tenant commands and other stations in the area also maybe helpful. Civilian laundries and dry cleaners often are required to make their marks a matter of record in the local police department. Assistance should be obtained from local police to identify the laundry or cleaning establishment when civilian-type markings are encountered. If such records are not maintained visits must be made to local laundry and dry-cleaning establishments. BLOODSTAIN EVIDENCE In crimes of violence, bloodstained evidence, if properly handled, is of great value. Sometimes the evidence may be found in the form of fluid or clotted blood More often, it maybe discovered in the form of fresh or dried bloodstains. Blood clots and bloodstains require careful examination since no blood clot or bloodstain is so characteristic in appearance that the investigator can definitely ascertain its origin. The body has a defense mechanism against excessive bleeding. As soon as bleeding starts in any great quantity, the blood pressure automatically drops and, consequently, the rate of bleeding slows. Blood normally begins to clot after 3 to 5 minutes. As it dries, the clot darkens in color until, when completely dry, it becomes reddish-brown or dark brown. An old, dried blood clot may become so dark as to be almost black. Because of mold, decomposition, or chemical changes, some bloodstains may appear to be black green, blue, or grayish-white in color instead of the usual reddish-brown. The color of the blood should be noted If the blood falls on porous material such as cotton, wool, blotting paper, porous brick, or soft wood, the original color may be altered by absorption of the blood into the porous material. A bloodstain on a dark background may be difficult to recognize. A flashlight may reveal the bloodstain even in daylight, for under artificial light a dried bloodstain may appear as a glossy or flat varnish against a dull background. Indoors, where the amount of light is limited, dried bloodstains on a dark-colored floor may be made more visible by shining the flashlight beam parallel to the floor rather than perpendicular. Shape, Persistency, and Age The shape of the bloodstains may provide important information about the circumstances of a crime. (See fig. 16- 12.) The height from which a drop of blood fell
Figure 16-12.-Bloodstains and splash. may be determined in many cases, from the appearance of the bloodstain. If the height of the fall is short-6 to 12 inches-the bloodstains may appear as circular disks on a smooth surface. If the height is from 12 to 60 inches, the edges of the bloodstain maybe jagged. This jaggedness of the edge of the bloodstains increases in direct relation to the height-the greater the height, the more jagged the edges. If a drop falls from a considerable height-2 or 3 yards-it may splash upon impact and form many small bloodstains, generally concentrated around a larger central bloodstain, giving a sunburst appearance. Drops of blood that strike a surface at an angle may bounce or splash, leaving a large initial teardrop-shaped blot with a series of smaller blots (similar to an exclamation point) trailing off in the direction of fall. Usually the larger splash is made first and the smaller ones afterwards. Do not make hasty conclusions concerning the direction of travel of the individual from the appearance of the bloodstains. Material upon which the bloodstain rests may alter the original shape of the drop as it strikes, and bodily movement actually may cause blood to fall in the direction opposite that of actual travel of the individual. Shape of bloodstains is also dependent upon the viscosity at the time it drops and the composition of the material it hits. Occasionally, blood may be identified on a garment that has been washed if the washing is not thorough. If, however, the laundering process is thorough involving the use of soap and hot water, residual bloodstain traces remaining usually cannot be identified as blood. Washing of the hands may fail to remove all traces of blood, especially under fingernails and around cuticles at the base of the nails. There are no criteria that enable the examiner to judge the age of a bloodstain with any degree of certainty. Clotting time may be altered by many circumstances or influences. Blood usually clots in 10 to 20 minutes. By examining the clot, you maybe able to estimate the time elapsed since the stain was made. Clotting is more rapid on a rough surface. Oily substances not only may increase the clotting time, but also may alter the appearance of the blood. Even the peculiarities of the blood of an individual may affect the clotting time. A single drop of blood that falls on a dry surface, such as a table or wood floor, usually will dry completely in about an hour at room temperature. Blood that has collected in a pool dries slowly depending upon the size and depth of the pool formed and the temperature and humidity to which it is subjected. Source Microscopic examination may sometimes disclose the origin of the blood because of the presence of foreign particles. Mucus or hairs from the nostrils may be found in blood from the nose. Semen and genital hairs maybe found in blood resulting from rape. Certain cells from the vagina may be noted in blood from menstruation. Although the presence of foreign elements or particles may lead to conclusions as to the place or origin of the bled, their absence does not necessarily disprove the fact that the blood originated in the part of the body from which it was believed to have come. Role of the Investigator You must be aware of what can or cannot be accomplished by expert examination of bloodstained evidence. You must realize that the value that may be derived from the examination of such evidence will depend almost entirely upon using proper methods in collecting, identifying, preserving, and transmitting the specimen to a criminal investigation laboratory. Marking Evidence Stained evidence that you have found should be immediately marked so you can positively identify it at any subsequent time. If feasible, place your initials directly on the evidence in an inconspicuous place away from the evidence stains. The marking of initials directly on evidence is applicable not only to clothing, but also to metallic objects such as axes, knives, crowbars, and hammers. An evidence tag should be attached to the evidence for further identification. If the evidence cannot be marked, the identifying data should be noted on the container in which the evidence is placed. Record all details of the marking of evidence in your notes. |
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