July 6, 2021
Which Is More Reliable: DNA or Fingerprinting?
In this Article
Fingerprinting Takes an Early Lead
Fingerprint identification has historically been the most trusted type of forensic evidence in criminal proceedings. But the first crack in fingerprinting’s veneer of infallibility came when tests revealed a substantial margin of error, including false-positive fingerprint identification. We have since become more critical of the opinions of fingerprint experts.
In fact, since 2002, a federal judge ruled that fingerprint witnesses can no longer tell juries that two fingerprints are a “definite match.” In criminal trials, it is now often the competence of each fingerprint examiner and the uneven nature of fingerprint recognition that are put on trial by defense attorneys.
In Defense of Ink Fingerprints
Fingerprints are still the most cost-effective and reliable way to identify people:
- They has been used for over 100 years to provide accurate identification of criminals.
- They have the most extensive database for identifying people, with tens of thousands of prints added to fingerprint databases every year.
- No two fingerprints have ever been identical in the many millions of comparisons.
- Fingerprints solve ten times more unknown-suspect cases than DNA fingerprinting.
Catch Me if You Can
Evidence from DNA has become an indispensable tool in fighting crime because it provides unambiguous identification of a criminal from minuscule traces of biological material left at a crime scene. As with fingerprints, though, in the absence of other evidence, an exact DNA fingerprint match does not amount to proof of guilt.
Since it was introduced in 1985, DNA fingerprinting has accomplished the following:
- Solved crimes considered otherwise unsolvable
- Put thousands of rapists and killers in jail
- Identified the remains of unidentified bodies
- Established paternity in countless cases
- Absolved wrongly accused individuals
In its short history, DNA fingerprinting has undergone greater scrutiny than any other method of criminal investigation, including ballistics, handwriting, lie detection, eyewitnesses, and fingerprinting.
The Drawbacks of DNA Fingerprinting
There are some problems with DNA fingerprinting though:
- Expense:
- Some DNA tests are relatively inexpensive. But for DNA fingerprinting to be admissible in court, the price skyrockets to $500 to $600.
- Backlog:
- Despite tens of millions of dollar in federal grants, there is still a significant backlog in the number of DNA fingerprinting tests waiting to be processed.
- Tampering with DNA Evidence:
- We can never discount the role of negligent or ill-meaning people in the lab or in the criminal justice system itself. But this criticism is true for any form of identification and is not unique to DNA fingerprinting.
Endgame: DNA Fingerprinting or Ink Fingerprinting?
Fingerprints are still the front-line evidence at crime scenes and at trial. With the breadth and depth of existing databases, this form of evidence will remain with us for some time, even if examiners must now testify that they have only found a “likely match.”
The new science of DNA fingerprinting is in its infancy and will continue to evolve. It is used by both prosecution and defense lawyers, to solve cold cases and exonerate the innocent. As technology changes, it will surely continue to be used in conjunction with other forms of evidence in an effort to develop the best form of human identification and help our police officers and federal agents bring criminals to justice.
Sources: Blood Evidence: How DNA is Revolutionizing the Way We Solve Crimes; Science 101: Forensics