Scientific Evidence

Overview of scientific evidence experts:
scientific evidence
1. Melendez-Diaz: confrontation right requires government to call witnesses who tested materials, if results are to be used in evidence; United States v. Blazier (Blazier II), 69 M.J. 218 (C.A.A.F. 2010).

experts may testify to meaning of machine-generated results.

-(Complex and evolving area, see Confrontation Clause Outline, Combined Deskbook vol. 3-tab T, p. 15 et. seq.)

2. DNA: TC: if you have it, get it tested, use it. Juries expect it, like it; “why not?” defense if untested; argue “what did you expect him to say, with DNA proving sex?” Can avoid using offender statement to prove sexual act element (you want offender on the stand).

{DC: sometimes good for you. Never stipulate to it. Can be useful cross-exam witness:
talk to examiner}

— where was it?

— other way to be there? Transfer during innocent visit?

45-14


— any past sex w/ accused, that could explain it?
— cannot tell age of DNA
— tiny sample (5 cells) gives result
— can not tell what biological source (body fluid or skin cells) yielded DNA14}