Logical Reasoning

PT143 · S3 · Q10 Television host: While it's true that

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Television host: While it's true that the defendant presented a strong alibi and considerable exculpatory evidence and was quickly acquitted by the jury, I still believe that there must be good reason to think that the defendant is not completely innocent in the case.

Conclusion

There must be good reason to think that the defendant isn't completely innocent.

Evidence

If the defendant were completely innocent, then the prosecutor wouldn't have brought charges.

Evaluate

By contrapositive, since we can tell that the prosecutor did bring charges (there was a jury trial), that would mean that the defendant was not completely innocent.

So, wait — did we just concede the conclusion to the author? That's the opposite of our goal.

The problem is, if we accept the conditional in the last sentence, we have no way to argue around the logic. It's the same problem we face in a Circular argument.

for example: Since no flavor of candy is as good as toffee, toffee is the best flavor of candy.

If we accept the premise of this Circular argument (no flavor of candy is as good as toffee), then we have no way to avoid drawing the conclusion that toffee is the best flavor.

That's why Circular arguments are cheating.

So the author's move in that final sentence feels like a Circular one in which the author is seemingly assuming the truth of the conclusion. Although technically it's not really circular since it's not repeating the conclusion; it's just inventing a ridiculous rule that prosecutors always have good reasons.

In real life, we would find the last sentence of this paragraph the most objectionable, because we don't have to accept that in 100% of cases where the prosecutor brings charges there is good reason to believe that the defendant is somewhat guilty.

Maybe there are dirty prosecutors who sometimes bring charges in order to exact revenge on the guy sleeping with their husband. Maybe there are complicit prosecutors who bring charges against a powerful person's political enemies, as a way to make those people look less trustworthy.

Goal

We can either look for an answer calling out the unfair premise in the final sentence, or complain that the author is undermining his own conclusion with acknowledgements like , or we can point out the possibility that the author's extreme premise could be wrong ... i.e., it's possible that sometimes prosecutors bring charges even though there isn't any good reason to think the defendant is somewhat guilty.

10.

The reasoning in the television host's argument is flawed in that the argument

takes lack of evidence for
Wrong Flaw Bad Conclusion/Premise Match
This refers to the famous Unproven vs. Proven False flaw. Does this author conclude that "a view is false"? Not really. I suppose we could say the jury had the view that "this defendant is innocent", but our author's conclusion is not that "the jury was wrong / the defendant is not innocent". It was more tentative: I still believe that there must be good reason to think the defendant is not totally innocent. Furthermore, the author's evidence definitely didn't say, "the jury had a lack of evidence to support its view". In fact, the evidence acknowledges that the jury had strong evidence for its view.
3% picked this
presupposes as evidence the conclusion
Not Truly Circular
This would feel very tempting to me, since our inability to fight the logic of this argument is due to the last sentence feeling unfair, like the author is assuming some rule because he wants to keep assuming that there's some good reason to think the defendant is somewhat guilty. But is the author assuming her conclusion as evidence? No, her conclusion is that "there must be some good reason to think the defendant is guilty" and her evidence never assumes "there is some good reason to think the defendant is guilty". Her evidence states that, "If a prosecutor brings charges, then there is good reason to think defendant is guilty".
14% picked this
Correct
places undue reliance on the
Why this is right
This is one of those rare birds in LR in which LSAT is allowing us more or less to object to the truth of a premise. They want us to complain that "the fact that a prosecutor brings charges does not guarantee that there was good reason to brings charges." Prosecutors might bring charges for other reasons (revenge, political favor, bribe) or they might just be bad at their job. Their assessment that there is enough evidence to bring charges might be an incorrect one, where there isn't good reason to think a defendant is guilty but in their minds there is. So this answer about undue reliance is just saying, "This author is overly confident in the idea that prosecutors never make mistaken or corrupted judgments about the quality of the evidence ... prosecutors ethically and accurately bring charges in 100% of cases".
Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.
75% picked this
confuses legal standards for guilt
Out of Scope: morally guilty
We're only talking about whether there is good reason to think that this defendant is legally guilty. This conversation has nothing to do with whether she is morally guilty or not.
5% picked this
concludes that a judgment is
Bad Evidence Match
This answer accuses the author's evidence of being one and only one premise: the defendant was quickly acquitted by the jury First of all, that wasn't a premise at all. It was a concession (counterpremise). Secondly, the author concludes that a judgment is suspicious merely on the grounds that the prosecutor thought it was worth bringing charges in the first place.
3% picked this

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