Logical Reasoning

PT103 · S2 · Q23 In a certain municipality, a judge

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In a certain municipality, a judge overturned a suspect’s conviction for possession of an illegal weapon.

Conclusion

The evidence of the illegal weapon was inadmissible.

Evidence

if evidence is collected → it's inadmissible during an illegal chase

The only cause for the chase was that the suspect ran from the cops upon seeing them, but running from the cops does not create a reasonable suspicion of a criminal act.

Evaluate

On Sufficient Assumption and Principle-Strengthen, we're all about looking for rules that prove the wording in the conclusion.

In this case, the conclusion is trying to prove "inadmissible" and we were provided a rule that lets us derive "inadmissible" (so we need to trigger this rule).

In order to trigger this rule, we have to establish that this weapon was collected during an illegal chase. Does the evidence establish that this was an illegal chase?

Nope. It suggests it was, but it never uses that wording.

What we know about this chase is that the only reason the cops chased the suspect is because the suspect ran away, but running away does not create a reasonable suspicion of a criminal act.

If we synthesized that down, what we know about this chase is that the cops did not have a reasonable suspicion of a criminal act.

Goal

Since we're trying to establish "illegal chase", it looks like the missing link in this argument is something like this:

did not have reasonable → illegal chase suspicion of criminal act

23.

Which one of the following principles, if valid, most helps to justify the judge's decision that the evidence was inadmissible?

  1. Flight from the police could

    Opposite

    This argument wants to believe that there was not reasonable suspicion (in fact, it establishes as much), so this answer is pushing in the wrong direction.

    4% picked this

  2. People can legally flee from

    Unrelated to Goal

    We need to establish that it was illegal for the police to chase, but this is a rule about whether it was legal for the suspect to run. Those are two different things. Also, this is not even a rule that allows to establish that the suspect was legally fleeing. It only has the power to prove someone wasn't legally fleeing. Legally flee ? not involved in crime at the time

    4% picked this

  3. Correct

    Police can legally give chase

    Why this is right

    "only when", just like only and only if, is a Necessary (right side) indicator, so this rule looks like this: police legally ? person's actions created a giving chase reasonable suspicion And of course, the contrapositive is what we need (the test just writes it this way to disguise its relevance): person's actions have not created a ? illegal to give chase reasonable suspicion Since the police were chasing simply because the suspect fled, and a suspect's flight is not an action that creates a reasonable suspicion of a criminal act, this answer establishes that it was illegal for the police to give chase. From there, we know that any evidence collected is inadmissible, so we've successfully proven that this evidence is inadmissible.

    Skill tested: Principle-Strengthen · how this choice captures the argument's function is the move to repeat next time.

    64% picked this

  4. Flight from the police should

    Nothing New

    We already knew from the background facts that flight from the police shouldn't be considered a criminal act, because we knew that it doesn't create a reasonable suspicion of a criminal act. If fleeing were itself a criminal act, then of course it would create a reasonable suspicion of a criminal act. It would be a criminal act. So this answer is an inference we could have already drawn from one of the premises. It isn't doing anything to help us with our goal of establishing that this was an illegal chase.

    25% picked this

  5. In all cases in which

    Negated Logic

    This is just performing an illegal negation (flipping the lightswitch) on the conditional we want. We were looking for this: if there was no reasonable ? illegal to chase suspicion of criminal act This answer is giving us the opposite of that: was reasonable suspicion ? legal to chase On Sufficient Assumption and Principle-Strengthen, we expect that the correct answer will often disguise our missing link by presenting it in contrapositive form (as the correct answer here did), while a trap answer or two might talk about the right ideas but put them in backwards or opposite order.

    3% picked this

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