USE OF ULTRAVIOLET LIGHT IN FORENSIC INVESTIGATION

The use of Ultraviolet light can be of great assistance in many forms of forensic investigation. Listed below are numerous categories which benefit from the use of UV light:

Alibis    Lipstick, dust, hair, seeds, and thousands of other items clinging unseen to one's person may prove effective alibis if innocently accused, or damaging evidence if guilty.

Arson    Fire creating ingredients such as kerosene fluoresce a bright blue or green. Gasoline, unfortunately, does not fluoresce.

Autopsies    An important aid in both personal identification and in determining cause of death, UV light fluoresces scar tissue and aids in determining its cause. That, due to X-ray, almost invariably glows bright pearlish / white; scars from radium fluoresce a bright pale blue; those from mechanical, electrical, heat or chemical injuries show no characteristic appearance under the lamp.

Burglary    The use of invisible flu pastes or powders at appropriate points of entry when burglary is anticipated or habitual. If left undisturbed, the paste or powder will remain active for more than a year. Prowl cars, security units and schools can quickly spot flu on clothing or hands of suspects. Home items of considerable value can readily be marked for both later identification by the owner as well as external application of pastes or powders.

Blackjack    Flu powders or pastes can play an important role in establishing the sequence of events or other facts regarding injuries or fatalities. Flu pastes applied to blackjacks will establish whether the injury was caused by the officer or one of the participants in a brawl or riot.

Bullet    Flu pastes can play a vital part regarding whether or not wounds received from firearms were caused by officers or other participating in a riot or other circumstances. Caution should be used when applying flu pastes to bullets and shells, for coarse granules in the paste may cause damage to the firearm or to the operator when the gun is used. Very thin pastes and fine powders generously dusted within a barrel will usually work well. Prior experimentation should be made so that each officer will know just how they will perform.

Censorship    Penal institutions scan mail for secret invisible message and reveal it under UV light.

Checks    Check alteration in any form is immediately and clearly detectable under UV light.

Coins    At the U.S. Mint, telephone boxes, parking meters and other vending machines are frequently marked with invisible powders for entrapment.

Documents    Analysis of documents under UV light will bring out faded signatures, erasures, changes in original copy and invisible markings or messages, since the latter are generally written with such fluorescent substances as quinine, lemon juice, egg whites, asprin, urine, acentaniled (cold tablets) or specially prepared inks. Document tampering can be detected by premarking of files with vertical or diagonal lines of invisible ink.

Dry Cleaning    Invisible marking, used by some dry cleaners, as well as fading marks can be clearly seen under UV light.

Dynamite    Wrappings of dynamite generally fluoresce intensely.

Ear wax    Cerumen usually fluoresces a bright blue to blue / green to blue / yellow. Most body substances fluorescence will be effected to some degree by the medical history of the individual involved.

 Espionage    Since espionage communications usually deals with the invisible, UV light will immediately expose the flu chemicals used in orders, the passing of information or other written information.

Explosions    Dynamite wrappings, candles, matches and other materials that go into the making of a bomb can often be isolated under UV light for more specific laboratory analysis.

Fabrics    Stains, secretions, lipstick, inks, flu powders and foreign matter. Even after cleaning or dying, many fabrics can be linked to the original event.

Fingerprinting    On multi-colored surfaces, invisible white or invisible green dusting powder is recommended. Fingerprint should be lightly dusted using the same technique as for ordinary fingerprint powder. Darken the room and the print becomes more brilliant while the multi-colored background becomes darker, giving greater contrast. If necessary, the print can be lifted with ordinary lifting tape. To photograph, use an ordinary camera (not a fingerprint camera) in a totally dark room with an F8 opening at 20 seconds, a K2 Wratten 2A filter is necessary on the camera. Only the UV lamp is used for illumination and is placed as close to the print as possible. Use any fast film.

Fire    Alarm boxes can be dusted with invisible fluorescent powders or pastes, unburned hydrocarbon oil, paraffin or almost any other wax. Since most persons sounding false alarms are known to stay in the vicinity of the alarm box, portable UV lights can be used to check hands and clothing of persons in the vicinity.

Firearms    Obliterated serial numbers easily seen under UV light. Light applications of powder and paste in the barrel will mark bullet with invisible ingredient and in turn, mark the wounded person with flu matter. Wounded not so flu marked were obviously injured by others, such as in a riot or prison rebellion.

Forgeries    Alterations, stains, erasures and other tampering becomes clearly evident under UV light.

Hair    Bleached hair will show a characteristic whitish flu. Rodent hairs have a bluish / white flu. Dyed hair is usually apparent as most hair dyes are flu. Some hair oils, as well as wigs, also flu, but experience and practice will enable one to isolate one from the other. 

Inks    Many substances can be classified as "invisible inks" and some are readily available to prisoners who may well have a practical use for them. Some are: saliva, milk soapsuds, urine, limewash from walls, aspirin, lemon juice, quinine, bisulfate, ferrous sulfate, and potassium ferricyanide.

Incarceration    In penal institutions and jails, secret messages are easily detected if UV lights are used to scan mail to and from outside contacts.

Kerosene    Sometimes used in arson. Fluoresces a bright blue.

Kidnapping    Invisibly marking aids can be of great service in apprehending the kidnapper. Ransom money can be invisibly marked for identification and the area surrounding the contact point dusted with invisible fluorescent powders. Banks equipped with UV lamps can aid in tracking the passer of money and the invisible powder on the shoes, clothing, hands or hair of a suspect can place him at any one of the significant places involved.

Laundry    Laundry marks, originally invisible or simply faded are immediately revealed under the rays of UV light.   Collars, cuffs, shirt tails and even the shirt front may reveal a previously visible laundry mark obliterated by action of salt water.

Lipstick    While not apparent under white light, lipstick traces on the skin will fluoresce red and orange. (Not all lipsticks fluoresce.)

Paper    Various types of paper appear quite different when viewed under UV light, although appearing quite similar in daylight. Some are very dark, while other types exude a rather bright flu. This effect can be used to indicate that certain sheets did nor did not come from the same source, such as anonymous letters, ransom notes, poison pen letters. Paper should always be examined both UNDER the lamp and directly OVER the lamp, thus allowing UV to penetrate the paper. Some ARTIFICIAL water marks are often made with stamps prepared in a wax medium, and the impression will then glow under a UV light.

Pastes  (Invisible)     May be used to mark auto parts, stereo car tapes, tools, door handles, steering wheels, control buttons, coins, skin and other items for identification and confirmation of sequence of events in which marked person played a part. Items that eventually end up at Pawnshops, Junk dealers and other places, can readily be identified right on the shelves, with more specific identification being inside the item in the form of an invisible signature.

Peeping Toms    A thread, two feet high and easily broken, can be treated with invisible flu powder and stretched around the appropriate window. Any suspect in the area can readily be checked with a UV light for the line of fluorescence two feet above ground.

Pepper Spray   Some of the newest pepper sprays will leave a invisible residue on a assailant that can be illuminated with the use of an ultraviolet light.

Psychics     "Ectoplasm" or  spirit faces and other phony props used by these practitioners are immediately exposed under UV light.

Rape    Semen stains fluoresce a bright bluish / white under a UV light and will retain such capability for years. The background material of cloth, its natural flu and color must be taken into account during analysis. Microscopic studies should be made for confirmation of that observed under  a UV light. Semen stains also phosphoresce a bright green for a couple of seconds after exposure to short wavelength UV light. Gynecologic stains flu, often like those of male fluid.

Teeth    Natural teeth fluoresce pearly white. False teeth fluoresce a very dull green or not at all. False teeth designed several years ago may appear dull purple or black under UV light.

Time Cards    Dust edges of a "controlled" group of cards among which should be those of the suspect. At the end of the shift, place all untreated cards under a UV light for inspection. The presence of flu powder on any untreated card will indicate a good suspect. A trace of another color should then be placed on the suspect's own time card to determine if, indeed, he is punching in another's time card. Time factors naturally involved along with the flu powder should prove conclusive.

Transactions    In narcotics, kidnapping, blackmail, counterfeiting, gambling, smuggling and other crimes in which it is essential to prove the actual payment of money, the use of invisible flu powders are indispensable.

Weapons    All police weapons likely to be used in riot control, street brawls and other situations where it may become necessary to later establish responsibility for wounding, should be treated with pastes that will leave a definite flu mark upon the wounded person, thus indicating sequence of events in many cases and what agent caused the wound.

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