"Reasonable Scientific Certainty," the NCFS, the Law of the Courtroom," and that Pesky Passive Voice

In a posting last week about a proposed National Commission on Forensic Science recommendation for the Attorney General to take the position that an expert witness "is not required" to utter words like "reasonable scientific certainty" as a condition for the admission of the testimony, I discussed a set of cases cited in a public comment from a Commissioner. The author of the public comment wrote me that I was mistaken in at least one respect. He does not maintain that "Recommendation #1 would require the Department of Justice to argue for overturning existing law that 'seem[s] to require' these phrases in some forensic-science identification fields" and that attributing this view to him

takes my comment out of context and mischaracterizes it. My comments relating to the cited federal district court opinions stated that 'a number of federal judges apparently endorse -- and some still seem to require -- the use of these phrases in their courtrooms ... . I didn't argue that 'existing law' 'seems to require' these phrases in some forensic-science identification fields.'  Instead, I said that 'a number of federal judges ... seem to require' the use of these phrases. I think that it's fair to say that 'existing law' on this topic and what a given federal district court judge may believe existing law to be, are not necessarily the same thing. (In my experience they can be far from the same thing). Case law does not always (and often does not) translate into the law of the courtroom -- the way trial judges interpret and apply federal rules and case law in trial practice. That was the point I was attempting to make -- not that 'Recommendation #1 would require the Department of Justice to argue for overturning existing law.' That is clearly not the case. However, DOJ attorneys may nevertheless be required to utter those 'magic words' in a given courtroom and in a given case.

It certainly is true that some judges will want the proponents of the evidence to swear to its "reasonable scientific certainty." And, unless a higher court has explicitly ruled that this phraseology should not be used  -- as some have and as is appropriate for the reasons stated in a separate views document that the Commission is developing -- the trial judge may believe that he or she has the legal prerogative to make it "the law of the courtroom." The Commission recommendation recognizes as much, for it explicitly allows the prosecutor to put on such testimony when directed to do so by the judge in the case.

But does this judge's edict really have the status of "law"? Under the crude,legal realist perspective that the law is whatever the court says it is, I suppose one would have to call it "law." However, it seems clearer to call it a judicial practice that is ripe for change (without having to amend any rules of evidence or change any binding caselaw). To encourage this change, and to the extent that the passive voice in Recommendation 1(b) introduces ambiguity, it would be better for the Commission simply to say that "The Attorney General should direct all attorneys appearing on behalf of the Department of Justice ... (b) to assert the legal position that such terminology should not be required."