The transcripts of the Grand Jury testimonies about the shooting of unarmed teenager Michael Brown by Ferguson police officer Darren Wilson.

See, we use a scatter approach. And that is we use what's called an immunoassay. An immunoassay is an allergic reaction in a test tube to a class of compounds such as amphetamines, opiates, phencyclidine and so forth. What happens is we mix the sample with the antibody and if we get a reaction, then we know it is present or it is indicated as present.

That has to go on for further confirmation, which in our case is always gas chromatography mass spectrometry. And what that does is give you molecular structure identification. The molecules introduced into the instrument, and chromatography means separation. So gas chromatography means separation at the gas phase.

So what we'll do is separate out all of these compounds and then introduce them into the mass analyzer. The mass analyzer hits the molecule, sort of like my hand here, with very high energy causing it to explode and that gives you fingerprint identification. That's how we identify each of the drugs. We look to see the ions that are present, the ratios and so forth, other criteria that gives us the identification on that.

That is also quantitive, telling us how much is present. So that's the one part.

The other part is we run a gas chromatography for the other drugs and this will pick up everything from strychnine to ectasy, and pick all of those up on one screen. And unfortunately, we have even seen strychnine cases. If I didn't like you, that's what I'd use. That's a nasty poison.

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