Logical reasoning PrepTest 154 · Section 4 · Question 16

Incorrect. We don't have any data on people given an accurate verbal description, so this couldn't possibly be correct. We'd have to know how accurate those people are in order to determine whether or not eyewitnesses are more accurate.

Incorrect. This one's a little tempting, but then what explains the second experiment, in which only 38% of people satisfied the researchers' expectations by identifying a suspect? Unless the researchers changed how they framed their expectations, which the stimulus doesn't suggest they did, that second piece of data goes against this answer choice.

Incorrect. The researchers didn't direct people to lie. They just set up an environment in which it was easy to make a misidentification. So this isn't a proper description of what occurred.

Incorrect. This is out of scope. Nobody asked the test subjects to recognize similarities between the group of people in the lineup.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
In an interesting and frightening experiment, researchers showed witnesses video of a staged crime, then asked them to pick the suspect out of a lineup that intentionally did not include that person. 78% of people incorrectly identified one of the people in the lineup as having committed the staged crime. But when witnesses were told that their lineup might not include the suspect, they only inaccurately identified the suspect as being in the lineup 38% of the time.

Answer Anticipation:
Yikes. Even when they know they might not be looking at the suspect at all, almost 40% of people got it wrong? That's not good. But, back to the question at hand, this single study isn't enough to draw any big conclusions like "eyewitness evidence is totally unreliable." Expect a weak answer that is qualified with words like "can" or "might" or "tends to," and which identifies a possible phenomenon illustrated by this study.

Answer Explanation:
This does accurately describe what this experiment seems to indicate. If people are relatively sure the suspect is somewhere in the lineup, they think they see the suspect even when the suspect isn't present. If they know it's possible that the suspect won't be in the lineup, their expectations change and they are less likely to make a blunder.

Key Takeaway:
There are a solid handful of LSAT questions that use this format, i.e., describing a study in which one factor was changed between the first and second experiments, and the outcome drastically changed as a result. When you run into these, try to anticipate what this change alone allows you to infer. In this case, the low-hanging fruit would be something like "what people are told before viewing a lineup of potential suspects can affect their likelihood of misidentifying a suspect." Even if the answer choices don't include your exact anticipation, remembering to take this step will insulate you against trap answers.