Judge Questioning Expert Witness Judicial Misconduct: Cal. Appellate

A trial judge who bolstered the prosecution's expert witness through direct questioning committed prejudicial misconduct, a California Court of Appeal has ruled, finding clear bias in the judge's criticism of the defense for failing to hire its own expert witness. In reversing judgement, the appellate court concluded that the trial judge's jury instruction to “not speculate about anything that I think” failed to dispel the prejudice that he created.

In People v. Williams (Cal. Ct. App., Jan. 27, 2021), the victim was driving back to his home when he saw the back door of his house open, and two men walking in the alley next to his house. He pursued them, but lost them as they ran and got into a red Mustang. The victim could only identify them as black men.

He reported the theft of jewelry, cash and video equipment to the police. The responding officer took latent fingerprints of the likely entry point of the thieves, a window that was broken open. A Department of Justice (DOJ) latent print analyst, Vivian Zhang, scanned the prints, ran them through AFIS, setting her parameters to limit the result to 100 matches. The first match returned was to Malik Williams, who had been arrested two years earlier.

[Ms. Zhang] then analyzed the latent fingerprints visually with a magnifying glass, compared them with defendant's known fingerprints, and determined there were sufficient points of commonality to conclude they were a match. There were sixteen points of commonality, but only eight were needed to make a match under DOJ policy.

The victim could not identify Williams, Williams did not have a red Mustang and none of the stolen property was found in Williams possession. The only evidence against him was that he had listed his address as 0.3 miles from the victim's home and the latent fingerprint match. Williams was charged with felony burglary.

At an Evidence Code Hearing before trial, the defense attorney, an assistant public defender, moved to preclude or limit Zhang's testimony. The trial judge chastised the defense attorney for not retaining an expert witness and complained about the Public Defender's office being inadequately resourced.

At trial, the defense counsel tried during cross-examination of Zhang, the prosecution's latent fingerprint expert witness, to raise substantial questions about her methodology, error rates in fingerprint matches and an error in her own report.

When the defense counsel asked Zhang if she had reviewed any of the other 99 results from the database search, she admitted she had not. The trial judge interrupted, asking if the system kept a record of the other results. Zhang replied that the system only did so for three days and she had not printed out the other results. The defense attorney asked if she had even opened the files, but the trial judge interrupted before Zhang had a chance to respond, stating “She has said a couple different ways now she thought they got a positive finding on the first one and she stopped looking at the other images after that.”

Almost every time the defense attorney attempted to question Zhang's opinion, her lack of documentation, her awareness of studies on the commonality between fingerprints, error rates in matches of latent fingerprints, etc., the trial judge objected that the questions were “argumentative and speculative”, or “That's been asked and answered.”

The appellate court found that many of those questions had not been asked nor answered. While a trial court can question a witness, the appellate court quoted People ve. Rigney that it is “ordinarily better practice for a trial judge to let counsel develop the case and to undertake the examination of witnesses only when it appears that relevant and material testimony will not be elicited by counsel.”

The appellate court saw clear bias on the part of the trial judge in pre-trial hearings where he repeatedly “criticized defense counsel for failing to hire an expert and expressed its frustration with the Public Defender's office for, in its view, inadequately resourcing the defense of not only the instant case but numerous cases.”

Even though Zhang had agreed to the validity of one study concluding that latent fingerprint analysis had an error rate of 2.5%, and that the only significant evidence against Williams was the latent fingerprint, the jury convicted Williams and the trial judge sentenced him to one year in county jail and five years of probation.

The appellate court found that the trial judge's involvement in the questioning of the expert witness and commentary at hearings were not simple error, that they bore “all the hallmarks of improper judicial demeanor and appear to be born of the judge's disapproval of the Public Defender's office.”

The appellate court unanimously reversed the trial court's decision.

Studies of latent fingerprint matches have come under increasing scrutiny with under reporting of error rates having been alleged. Convictions based solely on the testimony of one latent fingerprint expert witness, where the methodology is questionable, are reasonably suspect.