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DIRECTIONS FOR USING THIS CASE STUDY: This case study can be used in a number of ways. First, it can be given to a group of students who will analyze it and answer the questions below. Second, it can be used as an individual assignment, and, third, as a jumping off point for a class discussion.


The court was going to convene. Margaret Sackler was really frightened. It had been 5 years since she was attacked by William Bern and now he was asking to be released from jail on new evidence his attorney had found. She didn't really understand the evidence, her lawyer called it DNA fingerprinting.

Five years ago, Margaret had been walking in a parking lot outside a mall near her home. It was dark and near closing time so there weren't too many people around. A man had come up to her and asked for her money and jewelry, he had a gun. She had been told you don't fool around by trying to protect your valuables, so she gave him everything. But he started to beat her. She fought back, scratching him and hitting him. Her blood and his was all over her. Then a car passed by, her assailant got scared and ran. Who knew what he might have done to her if the car hadn't come by?

She identified him in a line up and testified at the trial. She had seen his eyes clearly but he covered the rest of his face with a mask. She would never forget his eyes. He was found guilty and sentenced to 25 years to life for assault. She finally felt safe.

The man had always claimed he was innocent so when he heard about DNA testing he asked his attorney to test the blood on the blouse Margaret was wearing. It was old blood, five years, but with a new type of DNA testing, called PCR, old DNA and small amounts can still be tested.

Margaret was asked to give a blood sample and all the samples were tested. His blood's DNA did not match the blood on Margaret's shirt. Now he was asking to be released pending a new trial.

Margaret didn't care---she was sure, he was the one. She'd never forget his eyes.


1. If you were the judge would you give this man a new trial? Why or why not?

2. What arguments would you give if you were the prosecutor (who is there to protect the victim and future victims) not to use the DNA evidence?

3. What arguments would you give if you were the man's attorney so the DNA evidence might be submitted and a new trial issued?

4. Margaret is an eye witness. Which is more reliable, an eye witness or scientific testing of DNA? Why?

5. Should DNA testing be used by already convicted persons to get new trials? Why or why not?

6. If DNA testing were reliable by only 85%, is this enough to release a man convicted of a felony? Why or why not?


Copyright 1995 Ronnee Yashon

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