The quality of a fingerprint is often in the eye of the examiner, they said, which can mean identifications are problematic.
"People leave behind all kinds of fingerprints, and the job of a forensic examiner is then to look at a fingerprint and identify a person who could have left it," engineering science Professor Akhlesh Lakhtakia said. "Various scenarios can be envisioned where a fingerprint can be seriously altered. Once it is altered, it can conceivably lead the examiner to a false conclusion."
Fingerprints are subject to environmental weathering and smudging, and its subsequent condition affects how reliable a match can be between a collected print and prints on record, the researchers said, so knowing a fingerprint's dependability can minimize the chance of a wrongful or delayed conviction.
Lakhtakia's team created a process using computer programs to grade a fingerprint for the availability of ridge detail for subsequent identification, ensuring standardized evaluation to a degree finer than any human can accomplish.
"The quality of a fingerprint can be graded finer than on a zero, one, two, three scale," Lakhtakia said in a university release Wednesday. "Two-point-three percent is worse than 15 percent, but both could be graded as a zero by the naked eye. Humans can't grade finer than the zero to three scale. But computers can."
The ease and relative speed of this computer-based grading system may help to standardize fingerprint quality assessment in an inexpensive, efficient manner, the researchers said.