It's an interesting argument. Is there a highly-credible, authoritative source? Maybe someone like the EFF or ACLU? There are lots of ideas online about the law, of varying credibility, and I'd hesitate to risk a lawsuit over Internet advice.
Everything in a US courtroom is adversarial; every witness is cross-examined and their credibility can be questioned.
>every witness is cross-examined and their credibility can be questioned
I think we're talking about different stages. The determination of his qualifications happens before he can be a witness for one party. I'm talking about voir dire. Before we even get him on the stand, there's a separate hearing to determine if he can even be an expert witness, and the opposing party can challenge.
Anyway, there is no ongoing action that I can find. It's only just come into effect, so that's to be expected. As far as an authoritative source for the argument: the person we're discussing is actually the author.