I’ve been reading Agatha Christie lately, and I guess I was surprised to see that even in the first half of the 20th century, fingerprints were considered important evidence at a crime scene. I can’t claim to be an expert on contemporary forensics, but from what I’ve seen in movies, fingerprints are usually scanned into a computer, and the computer does the matching.
What good, then, were fingerprints 80 years ago? Were there people whose job was dedicated solely to correctly matching fingerprints to the on-record fingerprints of known criminals? Also, where were the fingerprints stored? Was there only one copy of a criminal’s fingerprints? And, if that is the case, wouldn’t the place that stored those records be a target for criminals who want to destroy their fingerprints, so they could commit crimes more easily?
I imagine they would be used more for “We found some fingerprints, we arrested this suspect, let’s see if they match,” rather than trying to compare to some database.
Yeah. Even with a database for fingerprints, this is still how we use things like DNA, bite marks, ballistics, fiber, etc. today. Instead of using evidence to identify subjects, it’s used to confirm and convict.
The use is that if the police have a suspect, they can use fingerprints as evidence to convict him. They can show that this particular individual has handled this particulat weapon, for example.
I’d suppose that the records were held in Scotland Yard, locked in secure room and well guarded. Only an army of could conceivably break in to destroy the records.
My Mom was an FBI fingerprint clerk. She explained it to me like this.
If you had a complete set of ten fingerprints, you assigned each one a number based on its characteristics. Say 1/3/4/4/6–4/3/3/2/3
Then you could search all the fingerprint card files for only sets of ten that matched the numbers of that set. You went to the first card and looked at the first finger. Close? Then look at the second finger. Way off? Return card to file cabinet and go to the next one.
They actually did have databases. When arrested, they would take the fingerprint, so they could search through them later. There are various ways of classifying fingerprints so you wouldn’t have to sort through every single one. The 1.2 Classifying fingerprints and *2.3 Modern era *sections of the wikipedia page might be of interest.
I think the larger issue is the belief that database systems weren’t in use in the early 20th century. Now I didn’t say “computer database systems,” which obviously weren’t in use.
Take a look at the Library Science at Wikipedia for starters. That little grey-haired lady in your elementary school probably wasn’t a librarian, and most of the clerks at your public library probably aren’t, either.
They also would have compared prints of ‘likely suspects’ whose previous crimes matched the one being investigated, or anyone with a criminal past who may have had links to the victim etc. Much in the same way they assembled collections of mug-shots for witnesses to view.
The FBI has maintained a database of fingerprints since early in the 20th century. It’s just that before computers, it was all cards. My fingerprints are in that data base from several sources, so I am familiar with what used to be the procedure. Paul nailed it.
A few years back (maybe a decade) there was a pretty fair scandal when it came out that a fair number of the fingerprints in the FBI files were misfiled. I can’t recall the exact reasoning now, but the errors called into question a number of convictions.
Oh, I just talked to my Mom on the phone. She said a routine identification of an unknown person took about a week. A rush job on someone suspect of a crime might take three days.
I seem to recall that a lot of cold cases were reopened when computerized matching started and fingerprints from crime scenes were run though the databases and matches found.
Fingerprints go back farther than the 20th century – they were in use in the 19th, as stories by Mark Twain (Puddin’head Wilson) and Arthur Conan Doyle (The Adventure of the Norwood Builder) testify. as noted anbove, it wasn’t that you tried to look through a vast database to find matching fingerprints – you used them to confirm or deny that the print belonged to a given person or persons, based upon a set of individual characterists – “bridges” or "crossings’ – within the general pattern.
Nevertheless, I find it interesting that two early detective stories that rely upon fingerprint identification – The Sherlock Holmes story the Norwood Builder and R. Austin Freeman’s initial Dr. Thorndyke novel, The Red Thumb Mark, illustrate how a positive fingerprint identification can be completely misleading, and cause the arrest of the wrong person, if not combined with a careful consideration of the circumstances as a whole.
As for not being able to do anything without computers – the world functioned pretty well (if somewhat slower) in the absence of computers. In Frederick Forsyth’s thriller The Day of the Jackal, set in 1963, it is remarked that the French security system of registering hotel guests across the country by index cards was so efficient that they prided themselves on being able to rapidly produce records of anyone staying anywhere within minutes, despite the lack of computerization.
Fingerprints were also used to identify convicts during inprocessing. Prior to fingerprints, each convict was subject to a very lengthy measuring session, and copious records were created listing such identifiers as length of fingers and toes and ear size and other minutiae. With fingerprints being so unique, all that was required then was photos, general descriptions and the prints.
Why? Well, some very well-placed criminals could certainly PAY a patsy to serve time for them!
~VOW
This was the Bertillon system of identification, the legacy of Alphonse Bertillon.
Its limitations were exposed pretty convincingly in 1903 when Will West was brought in to Leavenworth penitentiary and, upon looking through their indices, they found that they already had a “William West” incarcerated. Moreover, he was absolutely identical to the newly-admitted Will West. Their Bertillion measurements were effectively identical. They took fingerprints of the two men for identification purposes.
Although contemporary reports claimed that they were unrelated, their fingerprints were extremely similar, and from the close similarity of appearance, investigator Joe Nickell concludes that they were probably identical (monozygomatic) twins. See his book Secrets of the Supernatural (even though there’s nothing supernatural about this case).
Even with computerized databases, fingerprints still often aren’t checked against databases. Back in the early 90s, for instance (when I was still living with my mom), our house was broken into. The police were able to pick up fingerprints of the perpetrator. We had a pretty good suspicion of who it was who did it. We knew that our suspect had been arrested before, and had his fingerprints on file. But they weren’t allowed to check the fingerprints they found against the ones on file, because that would have been a prohibited breech of the fellow’s privacy. All they were legally allowed to do with the fingerprints (so they told us) was to compare them against prints found at other crime scenes, so as to tie the crimes together.
Now, it may well be that laws on this (as on so many other things) vary from state to state. And it might be that this wasn’t a law at all, but merely the policy of the police department we called, in which case it might even vary city by city. So there might be some police departments who compare every print they find against every other print they find. But there are also some who don’t.