Effects Of Eyewitness Testimony On The Us Criminal Justice System

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Midterm Paper: The Effects of Eyewitness Testimony in the US Criminal Justice System On December 14th, 1982, Marvin Anderson was sentenced to 210 years in prison for crimes that he did not commit [1]. He was charged with rape, forcible sodomy, abduction, and robbery; these convictions were largely due to the eyewitness testimony made against him at trial [2]. During the investigation, a collection of photos was presented to the victim, where Anderson’s photo was the only one in color. Then, in a line up 30 minutes later, Anderson was the only one brought in whose image was shown to the witness in the original array. Unfortunately, the witness then identified Anderson as the perpetrator, which acted as very convincing evidence in the …show more content…

Despite knowing the unreliability of eyewitness testimonies, investigators still narrow in on suspects identified by these witnesses. To explain the effects of eyewitness testimony one can examine a few conditional probabilities:
Prob(Police investigate all leads/Eyewitness testimony) < Prob(Police investigate all leads/No eyewitness testimony)
Prob(Correct person convicted/Police investigate all leads) > Prob(Correct person convicted/Police do not investigate all leads)
Thus depending on specific numerical probabilities, it follows that:
Prob(Correct person convicted/Eyewitness testimony) < Prob(Correct person convicted/No eyewitness testimony)
Of course, eyewitness testimonies are not always unreliable and often can be crucial in correctly identifying the perpetrator of the crime, thus these premises and conclusion are not to be taken at face value, but as a way to conceptualize bad bias from eyewitness testimony. Mistaken eyewitness testimony causes a large amount of bad bias by shifting focus onto one specific defendant. With all the focus on one defendant, many cognitive biases come into play, such as confirmation bias and belief perseverance. If a witness passionately claims that someone committed the crime, investigators are likely to mold evidence to fit the case against that defendant, instead of identifying an alternative suspect who

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