Fingerprint Analysis

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Fingerprint Analysis

• (Famous Cases)

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Fingerprint Analysis

• Forensic investigators have been using
  fingerprint evidence as a source of
  identification of suspects for over a hundred
  years.

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Fingerprint Analysis  

• Early work was by visual analysis of very obvious
  prints left at the scene of a crime

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 Fingerprint Analysis

• Modern forensic scientists now have a range of
  techniques for finding prints, cleaning up and
  enhancing print images, and rapidly finding a
  match from a database using computer technology.
   

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 Fingerprint Analysis

• Fingerprint evidence is seen as one of the best
  types of physical evidence linking a suspect to
  an object or location or for establishing
  identity.

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 Fingerprint Analysis

• Therefore, the forensic investigator will always
  search for fingerprint evidence at the scene of a
  crime and at related locations, such as a
  suspect's home or car.

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 Fingerprint Analysis

• A fingerprint is the pattern of ridges and
  related characteristics found on the finger pads,
  the fleshy parts of the fingers used for touching
  and gripping.

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 Fingerprint Analysis

• Each person's fingerprints are unique and stay
  unchanged throughout life.

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 Fingerprint Analysis

• According to Sir Francis Galton, the
  nineteenth-century English anthropologist, the
  chances of two fingerprints being identical are
  as small as 64 billion to one.

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 Fingerprint Analysis

• In over a century of forensic fingerprinting, no
  two prints have ever been found to be the same,
  even those of identical twins.

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 Fingerprint Analysis

• Skin is never completely dry or clean grime,
  oil, and sweat on the finger pads create
  fingerprints whenever a person touches something.

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 Fingerprint Analysis

• That is why criminals, unless they are wearing
  gloves, leave fingerprints behind.

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 Fingerprint Analysis

• If their hands are bloodstained, then they will
  leave bloody fingerprints behind, an example of a
  patent (visible) print.

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 Fingerprint Analysis

• Plastic prints are fingerprint impressions made
  in a soft material like soap or dust.

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 Fingerprint Analysis

• Latent fingerprints are invisible, but the
  forensic scientist can visualize them though
  special lighting or with the application of
  chemicals.

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 Fingerprint Analysis

• Fingerprints have been recovered from all kinds
  of surfaces, even plastic bags.

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 Fingerprint Analysis

• It would be very useful to be able to reliably
  detect fingerprints on human skin.
• So far, this been very difficult to do if more
  than two hours have elapsed from the time the
  fingerprints were made.

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 Fingerprint Analysis

• Potential methods are being developed to recover
  fingerprints after longer time periods have
  elapsed.

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 Fingerprint Analysis

• A fingerprint found at the scene of a crime can
  be dusted with chemicals to make it easier to see
  and then lifted or photographed.

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 Fingerprint Analysis

• It is then compared with the fingerprints of
  known offenders stored in a computer database.

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 Fingerprint Analysis

• In the past fingerprints were classified
  according to the specific features that make up
  the unique pattern of each print.

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 Fingerprint Analysis

• With computerized storage and retrieval systems,
  however, classification is not really necessary
  as the computer can readily scan and match the
  whole pattern of thousands of prints.

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 Fingerprint Analysis

• The image of fingerprints found at the scene of a
  crime can readily be enhanced and clarified with
  scanning and digitizing technology.

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 Fingerprint Analysis

• This means that even partial prints can be of
  value in identifying someone at the scene of a
  crime.

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 Famous Case 1

• In 1892 Francesca Rojas, an Argentine woman,
  became the first person ever to be convicted on
  fingerprint evidence.

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 Famous Case 1

• When her two young children were found beaten to
  death, she tried to blame a man called Velasquez
  who vigorously denied the charge and, in any
  case, had a firm alibi.

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 Famous Case 1

• Investigator Juan Vucetich, who was intrigued by
  the relatively new technique of fingerprint
  analysis, found a bloody fingerprint on a bedroom
  door in Rojas' house.

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 Famous Case 1

• He sawed the portion away and then had the woman
  give an ink-print of her thumb.

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 Famous Case 1

• Even with only a basic understanding of
  fingerprint analysis, it was obvious to the
  investigators that the bloody print belonged to
  Rojas.

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 Famous Case 1

• She confessed to the crime when confronted, and
  admitted that she committed the murders to
  improve her chances of marrying her boyfriend,
  who was known to dislike children.

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Famous Case 1

• Rojas was sentenced to life imprisonment.

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Famous Case 2

• The brutal murder in 1905 of Thomas Farrow,
  manager of a shop in Deptford, near London, and
  his wife Ann was to become a milestone case in
  the use of fingerprint analysis in Britain.

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Famous Case 2

• Money had been taken and a thumbprint was found
  on the cash box.

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Famous Case 2

• The Criminal Investigation Department (CID) had
  already built up a file of fingerprints of known
  criminals, but this print did not match any of
  them.

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Famous Case 2

• A witness led the investigators to two brothers
  called Albert and Alfred Stratton.

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Famous Case 2

• A match was found between one of the men and the
  print found at the scene.

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Famous Case 2

• The court battle over the evidence was, however,
  lengthy.
• Much hung in the balance as it was the first time
  fingerprint evidence had been used in a murder
  case in Britain.

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Famous Case 2

• After two hours of deliberation, however, the
  jury found the two men guilty and they were later
  hanged.

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Famous Case 3

• In 1910, Thomas Jennings was arrested on
  suspicion of the murder of Clarence Hiller in
  Chicago.

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Famous Case 3

• The main evidence against him was fingerprints,
  and four experts testified at his trial.

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Famous Case 3

• However, fingerprint evidence was still
  relatively new and Jennings brought an appeal
  questioning its admissibility.

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Famous Case 3

• In a landmark judgment, the Illinois Supreme
  Court upheld the conviction, saying that
  fingerprints were indeed a reliable form of
  identification.

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Famous Case 3

• Jennings was sentenced to death and executed on
  February 16, 1912.
• He was the first person in the United States to
  be convicted of murder on fingerprint evidence.

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Famous Case 4

• Fingerprint analysis also played a role in
  convicting the man responsible for an audacious
  theft.

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Famous Case 4

• On August 21, 1911, Leonardo da Vinci's Mona Lisa
  was stolen from the Louvre Museum in Paris.

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Famous Case 4

• There was a clear fingerprint on the glass that
  had protected the painting.

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Famous Case 4

• Fingerprint pioneer Alphonse Bertillon spent many
  months trying to match the print to samples in
  his collection but to no avail.

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Famous Case 4

• Two years after the theft, police arrested
  Vicenzo Perugia in connection with the crime.
• His prints matched those from the crime scene.

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Famous Case 4

• Ironically, Perugia's thumbprint had been in
  Bertillon's collection all the time, but it was
  of his right thumb.
• The one left on the glass in the Louvre was from
  his left thumb.

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Fingerprint Analysis

• Criminals soon realized that fingerprints could
  be used to convict them and took evasive measures.

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Famous Case 5

• Some used gloves but others, like John Dillinger,
  a gangster who terrorized the Chicago area in the
  1930s, went further.

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Famous Case 5

• While on the run from authorities, he had a
  plastic surgeon burn off the outer layer of his
  fingertips with acid, in the belief that this
  would erase his fingerprints for good.

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Famous Case 5

• A tip off put the FBI on Dillinger's trail, they
  confronted him and shot him dead.

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Famous Case 5

• In the morgue, they discovered Dillinger's
  attempts to burn away his this fingerprints.
• He had not succeeded.

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Famous Case 5

• Fingerprints usually grow back and, in any case,
  go down through several layers of skin.

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Fingerprint Analysis

• Early fingerprint investigators had a tough job
  sorting manually through print records.
• Today, matching is accomplished with the aid of
  high-speed computers.

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Fingerprint Analysis

• The FBI began to automate print analysis in the
  1960s with AFIS, the Automated Fingerprint
  Identification System.

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Fingerprint Analysis

• The AFIS computer scans and digitally encodes
  fingerprint records into a database.

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Fingerprint Analysis

• It can match a sample, either a ten-print set or
  a single or partial print, by searching the
  database.
• Early versions of AFIS searched hundreds to
  thousands of prints a second now the speed is up
  to 500,000 prints per second.

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Famous Case 6

• One notable success for AFIS was catching Richard
  Ramirez, a notorious killer known as the Night
  Stalker.

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Famous Case 6

• He had committed a number of brutal rapes and
  murders throughout Southern California between
  1984 and 1985, entering victims' homes at night
  and cutting the phone line.

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Famous Case 6

• He would shoot any men present before raping
  their spouse, often in the same bed where the
  corpse was.

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Famous Case 6

• His final crime involved a couple in Mission
  Viejo, where he shot the man and raped the wife.

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Famous Case 6

• Fortunately, both survived and the woman saw
  Ramirez' car, while another witness got the
  number of the vehicle.
• The stolen car was found abandoned and a partial
  fingerprint was recovered from the vehicle.

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Famous Case 6

• The Los Angeles Police Department had just begun
  to use an AFIS system that could compare more
  than 60,000 prints per second and they found a
  match for the print in the car within minutes.

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Famous Case 6

• A photo of Ramirez, a 25-year-old drifter from El
  Paso, went out in the papers and he was
  recognized within a day by residents in east Los
  Angeles, who overpowered him when he tried to
  steal another car.

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Famous Case 6

• He was convicted by a jury and, on November 7,
  1989, was given 19 death sentences.

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Famous Case 7

• Palm prints contain even more detail on them than
  fingerprints, and helped solve the kidnap and
  murder of 12-year-old Polly Klaas in 1993.

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Famous Case 7

• The girl was enjoying a pajama party with friends
  at her home in Petaluma, California, when a man
  appeared through an open window with a knife and
  carried her off.

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Famous Case 7

• The FBI used special light sources and
  fluorescent powder to locate an otherwise
  invisible palm print on a bunk bed.
• They also had a description of the intruder from
  the other girls.

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Famous Case 7

• Torn children's clothing was found a few weeks
  later near a site where a man's car had rolled
  into a ditch.
• That man was Richard Allen Davis, who had two
  previous convictions for kidnapping.

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Famous Case 7

• A fingerprint expert was able to match the FBI's
  palm print found at the scene of the crime to
  Davis, who then confessed and showed police where
  Klaas' body was.

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Famous Case 7

• He was sentenced to death in 1996 for kidnapping
  and murder.