The opinion
Brown, J.
(dissenting). Notwithstanding this court’s reliance on the fleeting reference to “field testing” in Commonwealth v. Connolly, 454 Mass. 808, 831 (2009), I think that in order to “nullify” the effect of the admission in evidence of the high probative value laboratory certificate, the so-called practice of “field testing” requires more demonstrative evidence than an officer’s mere statement that he has done it. 1 I am of the opinion *193 that in the circumstances presented here I am constrained to follow the teachings of Melendez-Diaz v. Massachusetts, 129 S. Ct. 2527 (2009), and I would, therefore, reverse the defendant’s conviction.
Admittedly, defense counsel could have probed on cross-examination to ascertain the field testing protocol; however, he cannot be faulted for not having done so in light of his awareness that the Commonwealth would proffer as prima facie evidence the compelling, persuasive, inculpatory scientific laboratory certificate.-