Sherlock Holmes worked as a consulting detective in London with his partner Dr. John H. Watson, who moved in with Holmes to help pay the rent.  Holmes was a freelance detective as well as a forensic scientist, the first of his time.  Holmes is unlike anybody we would find working in forensics today because of his disciplinary crossing reach.

Holmes worked as a detective and as such used his sharp mind to “reason backwards” or to see the conclusion of a criminal act and be able to reason backwards to find the motive and the culprit.  But Holmes was much more than just a detective.

Sherlock Holmes also worked in the chemistry lab of a hospital, making him a forensic chemist.  Holmes “discovered” a test to detect hemoglobin, and hence blood, he did this in Doyle’s mind 13 years before it happened in the real world.  Holmes commented on the uniqueness of typewriters three years before any real life document examiners did the same. He is considered a pioneer in the use of forensic science.

Today forensic chemists do not do detective work in the field and detectives do not spend time in the laboratory examining evidence, these are two separate arms of law enforcement.  Sherlock Holmes was a genius at both as best described by Doyle’s quote from Holmes’ mouth expressing both processes in one eloquent statement:

“The process… starts upon the supposition that when you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth. It may be that several explanations remain, in which case one tries test after test until one or other of them has a convincing amount of support”

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The driving force of art forgery is the fact that art work created by certain artists is worth more than art work created by others.  If a work of art can be replicated perfectly by an art forger it is only worth less monetarily than the original because of who painted it not because the painting looks any differently than the original.  The same theory applies to forgers who create new art pieces in the style of a master, if the forgery is believed to be genuine it will be deemed priceless but if it is found to be a fake it is deemed worthless, regardless of what the piece of art looks like.

Forensic investigators, along with art historians and appraisers, are often responsible for determining if a piece of art is a forgery or not. Historians often use stylistic analysis to determine if a work of art is genuine or not, possessing large amount of knowledge about the styles, tool, brushstrokes,  techniques used by certain artists. There are a variety of methods used for forensic authentication of art work.   Some of the technical methods for revealing fakes include X-rays, UV lights, and IR light, which can be used to see under layers of paint to see covered up works, determine time period or the actual artist of the painting if an original signature has been covered up.  Chemical analysis and spectral comparisons can detect the components of paint to ensure that modern pigments were not used in supposedly old paintings.  Examination of the craquelure, the network of cracks that appear on old paintings, can be analyzed to ensure that the cracks were not artificially made and that they follow the grain of the wood onto which they were painted.

Art forgery sounds like a thing of the past, but art dealers claim that about 15% of art sold at auctions are fake, which means hundreds of people getting conned out of thousands of dollars.

For more information on art crimes  save the date, the Museum’s new art crimes temporary exhibit is coming on February 15th, 2010!

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Fingerprint residue contains natural salt secretions that corrode metals at the points where the salt contacts the metal. This microscopic fingerprint corrosion leaves a permanent mark on metal that cannot be washed away. The heat of the firing of the gun also does not alter these marks.

The new technique that has been established to visualize these types of prints relies on running electrical current over the metal object , such as a bullet casing or a gun, that has been coated with a fine toner like powder. When a charge is run down the metal object the fine conducting powder is attracted to these areas of corrosion revealing a powdered fingerprint.

This technology can also be used in fires to recover prints of metals exposed to very high temperatures.

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