Why are jurors asked if each element of a crime is proved, rather than the crime as a whole

Question

After seeing the State of Washington Jury instructions for manslaughter as quoted in this answer https://law.stackexchange.com/a/96079/388, I'm wondering why the instruction is "if... each of these elements has been proved beyond a reasonable doubt, then it will be your duty to return a verdict of guilty" (my emphasis)

Shouldn't it be all of the elements, taken together, rather than each one.

I'm thinking that the more elements there are to a crime the harder it should be to prove. Even if there is no reasonable doubt on any one element, in principle there could be a reasonable doubt when all elements are considered together.

For instance say a juror considers a doubt as a certain probability, and reasonable doubt to be any doubt of more than 1%. Then if they consider the probability that each element happened to be 99.5% they would say they have no reasonable doubt of any element, but by assuming the probabilities are independent and multiplying them they would find that the probability that the entire crime was committed to be only 98.5% and therefore say that they have a reasonable doubt.

Manslaughter is perhaps a bad example, because logically each element could not happen if the previous one did not. But the same logic seems to apply to many other crimes - for instance theft of livestock. It's possible someone took an animal without intending to deprive the owner of it, or that they had the intention but didn't actually take the animal. So if each of these elements is proved but only marginally beyond a reasonable doubt, then it seems that the offence as a whole should not be considered proved.

Answer 1

Your suggested phrasing may actually work against the accused.

Under the current approach, if the jury has reasonable doubt about any individual element, it must acquit. If instead the jury could just consider the elements more haphazardly as a whole, they could inadvertently overlook doubt about one of the elements on the strength of another related element. Forcing them to think through each element individually is seen to favour the accused.

canada

The Supreme Court of Canada sees the current approach as a rule that favours the accused (R. v. Bain, [1992] 1 S.C.R. 91):

The requirements — that the Crown prove each element of a charge beyond a reasonable doubt before there can be a conviction; that the accused cannot be required to testify and that the Crown and the trial judge may not comment on the fact that the accused has not testified — are examples of rules that favour the accused.

Further, reasonable doubt is not amenable to mathematical calculation or even analogy to probability. It is a wholly different kind of threshold. Reasonable doubt is binary, not a matter of degree. It is an error for a judge to liken reasonable doubt to a degree of certainty; doing so warrants a new trial (R. v. Bisson, [1998] 1 S.C.R. 306). If a juror has a reasonable doubt about an essential element of an offence, then the juror has a reasonable doubt about the offence. If there is no reasonable doubt about any essential element of the offence, then there is no way to aggregate bits of doubt that are not reasonable to come to reasonable doubt on the whole. (Importantly, I am not saying that the jury accepts or rejects each piece of evidence on the reasonable doubt standard. Evidence is considered as a whole when determining whether there is reasonable doubt in relation to each element of the offence.)

This is not a probabilistic exercise. No matter what probability threshold one might set, there would be doubts greater than that threshold that would nonetheless not be reasonable doubts if they were not based in the evidence or lack of evidence. The quality and source of the doubt, not merely its magnitude, are critical to determining the reasonableness of the doubt.

The Supreme Court of Canada has explained (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.

Answer 2

Practically: so they don’t overlook something

Please refer to @Jen’s excellent answer which cites judicial reasoning on the matter.

However, by reminding the jurors that they must consider each element, they are more likely to turn their minds to every element and consider it individually rather than overlooking one and accepting it as proven rather than deciding that the evidence proved it.

Answer 3

There is no literal difference in the meaning of "if all of A, B and C are true" and "if each of A, B and C is true", so there is no compelling reason to choose "all" versus "each". They both reduce to the proposition "A & B & C". There may be a psychological effect where ordinary listeners tend to lump things together – this would be especially true of the instruction say "if A, B and C". That could lead to legally false beliefs, such as if the victim died in Idaho as a result of an act in Washington, the accused is innocent.

It is true that the more complex the logical structure of the instruction, the more confusing it would be for jurors. I don't know if there are studies that check whether jurors tend to convict out of desperation or acquit out of desperation when instructions get confusing, but that doesn't matter, because jury instructions are not supposed to favor the prosecution or favor the defendant.

People do not in general have reasonable numeric theories of evidentiary balance, unlike Star Trek's Spock who can immediately intuit the odds of beating a Klingon in a fist fight to 6 decimal places. Therefore there is no number assignable to "reasonable doubt". A more serious problem is that the wording tends to lead people to think that the defense has a duty to prove innocence, to create doubt. The alternative standard of being "firmly convinced" is adopted in some jurisdictions, and is thought by some people to give experimentally better results (in mock trials). Since there are no numbers, the question of dividing by three is moot.

The theft vs. manslaughter instructions differ because the underlying laws differ. Manslaughter pairs a cause and effect (acting recklessly plus death) which can easily happen at separate times and therefore separate locations. Theft of livestock by definition only requires an action taken with a mental state. If you take without intent, you are innocent; if you form the intent but don't act on it, you are innocent.