Reasonable doubt of eye witness's need for glasses in 12 Angry Men

Question

In the 1957 movie 12 Angry Men two witnesses give testimony - an old man with a limp who claimed to see the accused flee the scene 15 seconds after the murder and a woman who claimed to witness the deed while trying to sleep. The old man's testimony was questioned because doubts were raised that he could've moved as quickly as he had claimed given his disability. One of the reasons that the woman's testimony was questioned is the jurors recalling her marks on her nose, which suggested she used glasses.

Considering these two points abstractly, the old man's mobility seems (to me) a basis for 'reasonable doubt' because it was deemed that his observable mobility was not consistent with his evidence. But for the woman it seems (to me) a reasonable explanation might have been sunglasses or reading glasses - as was noted by one juror. This means they're considering apparent evidence that could point to explanations other than short-sightedness.

Clearly juries operate according to their own internal logic and discussion based on the evidence they've seen. But in a broad and fairly legally abstract sense, is there any legal guidance or writings on jurisprudence about whether evidence of a potential reason to question a testimony (though it could also have a different explanation - let's say the likelihood is 50:50) should be considered valid basis for 'reasonable doubt'? Assuming all evidence has been presented and jury must now decide. Any authoritative reading references on this aspect would be appreciated.

For sake of clarity this is an abstract question and I am not currently sitting on a jury.

Answer 1

canada

Both of the concerns you mention may be taken into account by a juror when assessing whether the prosecution has proved an element of the offence (identity, in this case) beyond a reasonable doubt.

Note that the jury is instructed not to assess each piece of evidence piecemeal. They would not be assessing whether they believe the woman beyond a reasonable doubt, or whether they believe the old man beyond a reasonable doubt. They would be assessing whether the prosecution has proved beyond a reasonable doubt that the accused was the person involved in the incident.

Here are some sample jury instructions from the National Judicial Institute:

Now what does the expression “beyond a reasonable doubt” mean? A reasonable doubt is not an imaginary or frivolous doubt. It is not based on sympathy for or prejudice against anyone involved in the proceedings. Rather, it is based on reason and common sense. It is a doubt that arises logically from the evidence or from an absence of evidence.

...

I will explain to you the essential elements that the Crown must prove beyond a reasonable doubt to establish [the accused's] guilt. For the moment, the important point for you to understand is that the requirement of proof beyond a reasonable doubt applies to each of those essential elements. It does not apply to individual items of evidence. You must decide, looking at the evidence as a whole, whether the Crown has proved [the accused's] guilt beyond a reasonable doubt.

That model instruction is informed by guidance from the Supreme Court of Canada in R. v. Lifchus, [1997] 3 S.C.R. 320:

• the standard of proof beyond a reasonable doubt is inextricably intertwined with that principle fundamental to all criminal trials, the presumption of innocence;

• the burden of proof rests on the prosecution throughout the trial and never shifts to the accused;

• a reasonable doubt is not a doubt based upon sympathy or prejudice;

• rather, it is based upon reason and common sense;

• it is logically connected to the evidence or absence of evidence;

• it does not involve proof to an absolute certainty; it is not proof beyond any doubt nor is it an imaginary or frivolous doubt; and

• more is required than proof that the accused is probably guilty ‑‑ a jury which concludes only that the accused is probably guilty must acquit.

See also R. v. Ménard, [1998] 2 S.C.R. 109:

the standard of proof beyond a reasonable doubt applies only to the jury’s final evaluation of guilt or innocence and is not to be applied piecemeal to individual items or categories of evidence

Answer 2

united-states

Is there any legal guidance or writings on jurisprudence about whether evidence of a potential reason to question a testimony (though it could also have a different explanation - let's say the likelihood is 50:50) should be considered valid basis for 'reasonable doubt'?

Not much.

If a jury finds that reasonable doubt is present and enters a not guilty verdict, this ruling cannot be appealed.

But evidence of a merely potential reason to question testimony isn't enough to overturn a jury verdict of guilty. Credibility determinations are completely the province of the jury and generally will not be reviewed at all on appeal.

A decision regarding whether to believe that the testimony of a witness is true is called a credibility determination. A finding that the witness important to proving a case is not credible is one legitimate basis to conclude that reasonable doubt exists as to whether a criminal defendant is guilty of a particular charge.

But, as one judge in the U.S. District Court for the District of Colorado summed up the situation (at this link which has currently gone bad):

There is no law on judging credibility.

One model jury instruction for federal judges in the 9th Circuit states:

1.7 CREDIBILITY OF WITNESSES

In deciding the facts in this case, you may have to decide which testimony to believe and which testimony not to believe. You may believe everything a witness says, or part of it, or none of it.

In considering the testimony of any witness, you may take into account:

(1) the witness’s opportunity and ability to see or hear or know the things testified to;

(2) the witness’s memory;

(3) the witness’s manner while testifying;

(4) the witness’s interest in the outcome of the case, if any;

(5) the witness’s bias or prejudice, if any;

(6) whether other evidence contradicted the witness’s testimony;

(7) the reasonableness of the witness’s testimony in light of all the evidence; and

(8) any other factors that bear on believability.

You must avoid bias[, conscious or unconscious,] based on a witness’s race, color, religious beliefs, national ancestry, sexual orientation, gender identity, gender, or economic circumstances in your determination of credibility.

The weight of the evidence as to a fact does not necessarily depend on the number of witnesses who testify about it. What is important is how believable the witnesses are, and how much weight you think their testimony deserves.

Comment

The Committee recommends that the jurors be given some guidelines for determining credibility at the beginning of the trial so that they will know what to look for when witnesses are testifying.

See also Instruction 3.9 (Credibility of Witnesses) for the corresponding instruction to be given at the end of the case.

Answer 3

Other than in cases of jury tampering or violating the requirements of not seeking/using unsubmitted evidence, a NOT guilty verdict means that the prosecution failed to convince the jury to vote guilty.

Why doesn’t really matter, and any attempt to make it matter, eliminates the political purpose behind a jury. You can’t both say that they are free to make a judgment and then reject that judgement because you don’t agree with it.

It is up to the jurors to decide, for themselves, not for other jurors, whether they were convinced enough to convict.