I was watching CSI and i have a question?

Question

I saw that they checked if somone had fired a gun by GSR powder or somthing like that i was just wondering how long that would last on your body for them to be able to find!?

Answer 1

Depends on if your dead or alive.

Also depends on a lot of different circumstances beyond giving you any real answer here even if the subject is alive.

Answer 2

Usually not more than a few days. There is a fairly reliable GSR test that test for heavy minerals such as barium, lead, and antimony.

On a separate note, be careful what you believe on CSI. Most of the forensic stuff they do is stretched in one way or another.

Answer 3

Up to 2 days if you don't wash your hands, but it can also be found on clothing, shoes...

Answer 4

I am currently handling a murder case with GSR evidence as a defense attorney.  I can tell you that DAs don't like GSR.  They don't like it because when a shot is fired, especially from a revolver, it can be argued that the GSR got on the defendant not necessarily because the defendant fired a gun but because someone close to him did.  GSR gets everywhere with any gun but even more so with a revolver because a revolver is more open than an automatic.

In my case there are two kids in a car.  Both fire a gun.  Later than day, both are arrested and tested for GSR.  GSR is found on one kid but not the other.  The reason?  My guy washed his hands.  What's odd though is that my guy told me that they both washed their hands, but obviously I'm not going to take that issue up with the DA.

Anyway, the short answer is that GSR comes off skin really easy.  Off clothes, you would have to launder them.  GSR also gets everywhere, so with co-defendant cases especially, it's becoming less favored by the prosecution.