Talk:Bloodstain pattern analysis

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Wikipedia:Ownership of articles I have left the following link for 66.141.34.101.

This article, particularly the intro, reads more like a sales pamphlet about the topic than a serious encyclopedia article. It's pretty poor but I'm not the person to fix it. Anyway, just in case anyone who knows about the subject sees this, can someone explain to me how the whole point/area of convergance analysis is accurate if you take into account that any blood which is flying in an area with gravity will follow a parabolic arc? It seems to me that using straight line analysis (i believe investigators simply use string) will always overstate the actual height of impact which, incidentally, will often be advantageous to the prosecution's story if there's a factual dispute (eg was it a fall or a beating). Just wondering Psychobabble 23:56, 7 February 2006 (UTC)

==Psychobabble doesn't seem to understand the topic, and his comments are not reflective of the article itself, which is fairly high-quality and explains the topic in great detail. The tone needs work, however, and I have included a note to that effect. If Psychobabble wants to understand how investigators deal with the problem of parabolic trajectories, he should look up ballistics, as it deals with the same field and the same issues. Don't insult what is an otherwise a good article by trying to raise doubts where there are none.

I think the tone issue you identified was what I was getting at, 'tone' was my only criticism of the article. I wasn't criticising the content of the article in the other part of my statement, I was seeking an understanding because that was an issue raised in a crim law documentary I saw. You're right, I don't understand the topic which is why I asked the question and it was a question I saw raised elsewhere in the context of an investigation where trajectories were measured using straight line string. Feel free to enlighten me as to how this issue is dealt with in real life :) This article didn't clear it up for me which is why I asked originally. Psychobabble 04:06, 25 September 2006 (UTC)

Psychobabble, you are correct about bloodstain analysts using straight lines to approximate the path of the bloodstain trajectories. This is called the tangential method. An analyst tries to use fast upward moving stains whose flight path has had little or no effect due to gravity. The resulting area of convergence will always have a height greater than or equal to the event. There are computer programs like HemoSpat that do the calculations through digital imagery and on-scene measurements so the analsyt doesn't have to use real strings. As for the tone of the article, I tried to cover what I could at the time and I'm sorry for not getting back to tidy things up. I will look at making it more encyclopedia-like. Kevin Maloney 14:12, 29 September 2006 (UTC)

Thankyou. Psychobabble 21:49, 29 September 2006 (UTC)

MVIS and HVIS?

Whats inbetween the two? It goes from 7.5 meters a sec, to 30+ meters a sec. Whats going on between the 50 feet that are left out?

There are different ways of categorizing bloodstains. The method presented here is what is currently accepted by the IABPA. These definitions were created years ago and were based on studies done by some of the pioneers in bloodstain analysis. The MVIS categroy is meant to cover most blunt force attacks and show the restriction of how fast you, as the assaulter, can punch, kick, swing a hammer etc. The HVIS category is more of a mechanical based attack such as chainsaws, machinery, handguns, etc. However that being said, categorizing impact stains as LVIS, MVIS, and HVIS is only a guide. There are always exceptions like sneezing blood which can produce HVIS-like staining. Hope this helps. Kevin Maloney 14:27, 29 September 2006 (UTC)