CLPEX Chat Board

Could someone point me in the direction of any articles written about the success rate of developing friction ridge detail off of firearms please. We are working on some possible workflow changes and was wondering if there was any research out there in regards to this topic.

Thank you very much!!

Anything newer than 1997? Wasn't Boston's Crime Lab having good results in the early 2000s?

L.J.Steele wrote: ↑Thu Nov 08, 2018 8:45 am Anything newer than 1997? Wasn't Boston's Crime Lab having good results in the early 2000s?

Every few years this topic comes up. Here's a thread from 2010 that has some information regarding Boston PD's recovery rate. However, it sounds like it did drop a bit after the article that referenced the 32% rate came out. I don't know if anyone still works there from when they were tracking their results, although Andrew Reitnauer did participate in that thread at the time.

I found a Technical Note article in a 2012 JFI discussing results of latents from Firearms over a two year period from the Denver Crime Lab. We are just looking into MAYBE making some changes into workflow and if processing firearms for latents is worth it. We can just send them to firearms and we would process the magazines. Not sure we will end up doing this, it was just something that was tossed around.

Thank you all for your replies.

Whether or not it's worthwhile is going to depend largely on what processing resources you have available to throw at the problem. The new Recover LFT technology that Foster + Freeman is advertising now might mean a significant improvement if it works as advertised but not everyone has the budget for that.

Currently just using CA/R6G and Laser. We are currently in the process of moving to a brand new lab (in about 1 year), repairing a laser and our big humidifier just went down. Don't think we have the budget currently for any new instrumentation.

The ability to develop and recover latents from a firearm, in my opinion, depends primarily on how was it handled and how much was it handled when it was collected. Was the person collecting it wearing gloves? If they were wearing gloves, were they wearing latex or the puncture resistant frisking gloves? Did the person clearing it handle it as little as possible or did they put their big old paws all over the slide and cycle it nineteen times to you know, make sure it was clear? Did they stuff it in their waistband to "secure" it temporarily while cuffing somebody? Is it a Glock or Hi-Point? Never had much luck with either. Rugers for some reason, if I ever developed anything on a trigger, chances are it was on the trigger of a Ruger. I had better overall luck with some of the older chromed out slab sided Saturday night specials a la Charter Arms, Phoenix Arms, or similar.

Minnesota lab stats in paper attached. List of other publications:

With respect to latent print recovery rates, recovery rates on firearms and ammunition in actual casework have been reported elsewhere (Barnum and Klasey 1997; Johnson 2010; Pratt 2012; Maldonado 2012). These sources noted consistent recovery rates of 11%, 12%, 10%, and 13%, respectively, for firearms or magazines from firearms, depending on the study. We wish to contribute to those data as well, while adding another layer of information by further subcategorizing our firearms, as was done by Pratt (2012).

My brower is warning me that the Langenburg attachment is unsafe to download. Anyone know what's up?

I didn't get an error. What specific error you are getting and are you on a personal computer or one associated with your work?

Boyd Baumgartner wrote: ↑Thu Nov 15, 2018 8:31 am I didn't get an error. What specific error you are getting and are you on a personal computer or one associated with your work?

I also got the error at my desk, using Internet Explorer. However it did allow it using Edge.

L.J.Steele wrote: ↑Thu Nov 15, 2018 7:19 am My brower is warning me that the Langenburg attachment is unsafe to download. Anyone know what's up?

I emailed you the attachment directly.

I can't imagine getting to the point where firearms aren't processed for latent prints as a matter of course. Even the idea of not processing Glocks or Hi-Points seems crazy. In the past 6 months alone, I've found 2 identifiable prints on triggers and ID'd one of them. While my success rate for firearms isn't as high as plastic bags, I still routinely get ID's (or at least find identifiable latents) on all types of guns.

I'll see if I can gather some data for people.