Best legal practice insists that those accused of crimes should have the absolute right to see all the evidence gathered against them and to have opportunity, in the case of technical evidence of any kind, to be able to have it tested and evaluated by their own experts.
The ICTY chose not to comply with this practice. The DNA evidence put forward in all its major trials was no more than a reporting of findings backed with computer printouts that in themselves were proof of nothing. Primary DNA samples were not provided to the court. Nor were precise details of the methodologies used. There was no information about the precautions taken to prevent problems such as contamination (a huge problem in DNA work).
The court therefore reached verdicts, for which DNA evidence was crucial, on the basis of a management report of the DNA work. This was effectively uncorroborated hearsay evidence which could not be tested in any meaningful way.
This section gathers together some of the many detailed concerns raised on this matter.