Looking at the labyrinthine convolutions of my ears compared to others got me to thinking:
A) Assuming an alternate history:
- Photography has not been invented. Drawing/painting exists but that seems somewhat slow and non scientific.
- Forensic evidence at the scene to identify the culprit is not well developed. Instead what is important is identifying current convicted criminals as being the same person as prior convicted criminals - perhaps there is some kind of three strikes law in effect motivating this.
- Either fingerprints have not yet been discovered/legitimized or perhaps the people in this history have no fingerprints. Similarly, genetic evidence has not yet been developed.
- Making ink prints of body parts is available, as is measurement of body parts by ruler.
How do ear prints compare as an identifying method compare to other biometrics / other simple methods?
B) In our own actual history, before fingerprints and photography, how were repeat offenders identified?
I think a lot of it comes down to the effectiveness of the measuring tools used - I understand that 3D laser scanning of ears for the purposes of biometrics is showing promising results.
For law enforcement though, assuming it’s for identifying someone you have in custody and have had in custody before, I would have thought retina scans would be just as good, if not better, because ears can be modified by their owners more readily than retinas.
There have been convictions based on ear prints left by criminals at crime scenes, so I guess that adds weight to the notion that they could be reliable enough for biometrics. For crime detection though, they’re obviously not going to supplant fingerprints in many cases, because criminals are significantly less likely to leave ear prints at a crime scene. (I realise you weren’t asking that, but felt like mentioning it anyway).
Scientists are developing methods of using ear prints to identify criminals. The main disadvantage is that people generally don’t leave ear prints at the scene of the crime, plus the fact that it hasn’t been conclusively proven that ear prints are unique.
In actual history, there were just physical descriptions. By the late 1890s, the Bertillion Method of measurements. Bertillion was dropped because, while it was useful, it had too many variations depending on who was making the measurements.