View Full Version : Forensic Research

02-08-2009, 09:13 PM
Does anyone know of any resources where I can find out the length of time it takes to do DNA tests on blood; also I need to know how long it would take lift a finger print off a bloody i-pod.

I've read forensic books that say 99% of crime fiction/drama it happens too quick. I don't want them saying it about my book!

02-08-2009, 10:57 PM
Actually lifting the latent takes seconds, although there is prep before hand. After the bloody iPod is photo'd, inc w/ a scale (a ruler) the pritns are often exposed to gas created by (honest) putting crazy glue on pipe cleaners in a hood (upside down paper bag) which makes the prints stand out even more. Then the print make be dusted (carbon dust applied w/ feather duster-type brush) and the print is actually touched w/ a 2" piece of tape similar to commercial Scotch tape. Lifting the tape lifts the dust that adhered to the now-hard ridges and whorls of the print (hard from the gas exposure) and the tape is applied to a clean paperboard the size of an index card.
All this can be done in the field, by an average grunt ofc.
As far as the lab, if it's a pvt citizen paying a pvt lab, turn around can be w/in a week (although realize that getting a hit depends upon the right answer already being on file*) but pol labs are usus backed up for months.

*for ex, if your blood is on the iPod but they have no sample of you to which a comparison may be made (no body, you're off posting on the 'net, perfectly alive) and they don't have your parents or some blood rel with which to make a partial comp, then they have the sample waiting for a match...they can only say it's you once they have your sample or both your bio parents.

02-08-2009, 11:19 PM
Thank you so much for that. Fascinating.

A book had hinted that it would be around a week; I didn't want to do the typical fiction thing of having the evidence within hours/next day. I do it want to be right.


02-09-2009, 06:45 PM
As Horseshoes said, the DNA test and the fingerprint comparison in AFIS don't take long at all, It's the backlog that takes the time. Depending on how high profile your case is, if you are sending your sample to the state lab, figure on a one to three month wait. If you're in LA or NYC (and according to CSI, Miami and Las Vegas) they have their own DNA analysers. Smaller cities can't afford equipment on that scale.