The right to a fair and impartial jury is a fundamental principle of the American criminal justice system, and the state's Supreme Judicial Court recently explored this principle in a case concerning whether a criminal defendant was disadvantaged when a blind person served as a juror in his trial for assault. WGBH Morning Edition host Joe Mathieu spoke with Northeastern University law professor and WGBH News legal analyst Daniel Medwed to take a deeper dive into the case and the SJC's decision. The transcript below has been edited for clarity.

Joe Mathieu: Let me just start with the basics on this case. This one is pretty fascinating. How did the jury issue crop up to begin with?

Daniel Medwed: Here's what happened. Back in 2015, without warning, one man punched another man in the face, breaking his orbital bone and his cheekbone, not to mention causing some retinal bleeding and nerve damage. The legal issue in the case was not so much a whodunit — the men knew each other, there was no question of identification or misidentification, and there was no real dispute about whether a punch was thrown.

Rather, the issue was whether these injuries rose to the level of being a serious bodily injury, which is an element of the applicable assault and battery statute that this man was facing. He was charged with that crime. The way the jury issue cropped up is during jury selection, the trial judge interviewed a prospective juror who happened to be blind, came away convinced from that interview that the juror was qualified and competent to sit on the jury. The defendant at the time didn't object. But after he was convicted, he claimed on appeal that the presence of the blind juror deprived him of his right to a fair trial.

Mathieu: So what are the rules around all this? We all get jury summons, but what what are the rules for eligibility? How does it work for people, at least in this case, with physical disabilities?

Medwed: Massachusetts law is fairly clear on this: Every person who is otherwise eligible shall have an equal opportunity for jury service. That means you can't be excluded on the basis of race, religion, gender, national origin, economic status or occupation. Also, with respect to physical disabilities, the law provides that, "you shall serve except where it's not feasible to do so." What that means in practice is that judges must scrutinize prospective jurors with physical disabilities, determine whether it's workable, whether it's feasible for them to be impaneled on a particular case.

Mathieu: So what did the SJC decide here in terms of upholding the judge's decision? And what's your opinion?

Medwed: Well, the SJC did uphold the trial judge's decision, finding that this comprehensive interview was sufficient to justify a finding that the juror was qualified to sit on the jury. And I think it was the right decision.

For one thing, it reinforced a fundamental principle that all people — including people with physical disabilities — shall share fully and equally in all aspects of our public life. For another, the defendant here did not seem to be disadvantaged by the presence of this juror. As I noted before, identification wasn't an issue. The injuries were largely internal, not external, and had healed by the time of trial, so there was not much to actually see at trial. Moreover, to the extent that photographic evidence was part of the case, the juror had indicated during that pretrial interview that he would feel comfortable simply having other jurors describe the contents of those pictures.

Mathieu: So that was addressed?

Medwed: That was addressed.

Mathieu: But there might be cases in which a blind juror is not admissible.

Medwed: I think that's right. Let's imagine a situation where the defense is claiming mistaken identification — that the defendant is innocent and they found a third party suspect. And the crux of the defense argument is that the defendant resembles this third party suspect and they're asking the jury to compare the physical attributes of the two to suggest that the police and prosecutors got it wrong. In a case like that, possibly it might not be feasible to have a visually impaired juror. That said, I think the Massachusetts approach is very sound. The default rule should be that everyone shall [and] must serve, including people with physical disabilities, unless that presumption is rebutted with evidence that it's not workable, that's inclusive, that's egalitarian. And it's probably the way to go.