Is Fingerprint Evidence Becoming Less Conclusive?

Fingerprints have long been seen as an infallible form of evidence, but in reality fingerprint evidence is only as good as the fingerprint examiner and quality of the print.

Experienced criminal defence lawyers will be able to give numerous examples of receiving ‘expert reports’ from fingerprint examiners (often employed by the NSW police service) who declared a fingerprint match, and then managing to discredit that evidence through the use of experts of their own.

The perceived infallibility of fingerprint evidence is being further called into question by the purported development of new technology making it possible to effectively clone fingerprints.

Last month, a member of a German computer hacking group claimed to have developed a way to successfully clone a fingerprint from a photograph. The hacker claims to have replicated the fingerprint of a German politician from close-up photographs taken of her at a press conference using a standard camera.

The ability to clone a fingerprint could have a number of implications, for both security and the courts. Fingerprints are often used in court as evidence and fingerprint technology is increasingly being used for security purposes in the technology industry and even in politics, with voters in Brazil being required to provide their fingerprints as identification at the last presidential election. If it turns out that it is possible to fake fingerprints from a photograph, there could be implications for personal security as well as the legal process.

How reliable is fingerprint evidence anyway?

Fingerprint evidence is often relied on in court along with other forms of forensic evidence obtained at the scene of an alleged crime. Fingerprint evidence first started being used in law enforcement during the late 1800s, and since then has become a very common form of evidence.

There are a number of reasons why fingerprint evidence is so widely used in court. Everyone’s fingerprint is unique, even in the case of identical twins, and the patterns and ridges provide a way to differentiate one person from another. It may also difficult for those who commit crimes to avoid leaving fingerprints at the scene of a crime, and with a database of thousands of fingerprints, if there is a match with a print found where a crime has been committed it can serve as a connection between a suspect and the crime.

The reliability of fingerprint evidence has been called into question over the years, along with other forms of forensic evidence like DNA evidence and handwriting analysis.

Fingerprint evidence is often presented as infallible, a myth that is often reinforced by crime shows and movies. Fingerprint and DNA evidence is not infallible and can be subject to misinterpretation and human error.

If defence lawyers fail in their duty to properly investigate the accuracy and reliability of forensic evidence, it can lead to juries accepting it as truth and convicting innocent people.

Fingerprints don’t just involve the tips of the fingers; the whole hand has a pattern that can be used as an identifier. Fingerprints are usually formed partially from sweat and grease on a person’s hand, which leaves an impression on a hard surface. When a fingerprint is found at the scene of a crime, a copy is taken and then compared against a database of fingerprints taken from people who have been accused or convicted of a crime previously. This narrows down the search, and the final identification is done by humans who compare the two sets of prints visually to spot whether or not they match.

This process is open to error, especially where there are only partial fingerprints gathered, or where the prints are smudged and are therefore more difficult to read.

Just because a fingerprint is found at the scene of a crime doesn’t necessarily mean that the person whose print it is was involved in the crime. And if a print is found and matched, it is not 100% accurate. False fingerprint matches do occur from time to time and studies have shown that they have the potential to lead to wrongful convictions.

What impact could these new developments have on criminal cases?

The idea that fingerprints could be cloned and reproduced through a photograph has the potential to seriously impact the integrity of fingerprinting technology and its use as a reliable form of evidence in court. If such technology were to become mainstream, an offender could use someone else’s fingerprints to frame them for a crime or simply as a way to divert suspicion and attention from themselves.

It could also potentially lead to serious security breaches or even place public figures like politicians and celebrities at risk of being falsely accused of crimes. With developments like these, and other ways of mimicking fingerprints, the evidence that was previously provided by fingerprints may well become even more inconclusive in the future.