What are the primary DNA analysis techniques that have been used since 1985?

What will be an ideal response?


In 1985, Alec Jeffreys and his colleagues in England first used DNA in a criminal case. Shortly thereafter, DNA evidence began making appearances in trials in the United States. Initially, DNA analysis was hampered by the need for a large enough sample and by the fact that the manual processing technique called Restriction Fragment Length Polymorphism (RFLP) took up to 14 weeks on average to produce results, but the technique was good and produced great results. Technological advancements led to a new type of DNA analysis known as polymerase chain reaction (PCR), which takes small samples of DNA and reproduces as many copies as are needed for adequate analysis. Short tandem repeats (STRs) are even smaller pieces of the DNA helix (ladder) that can be reproduced using PCR to produce multiple copies in an instrument called a thermocycle. PCR-STR takes about 24 hours to extract the DNA from an evidentiary sample and only 2-3 hours to type the DNA using automation. It works well on degraded samples and on analysis of old cases.

Criminal Justice

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When interviewing the victim of a sexual assault, ____________________ questions should be asked that allow the victim to describe the events in his or her own words

Fill in the blank(s) with correct word

Criminal Justice

New punishment options developed to fill the gap between traditional probation and traditional jail or prison sentences and to better match the severity of punishment to the seriousness of the crime are known as ________.

What will be an ideal response?

Criminal Justice

The Supreme Court’s refusal to rule on the merits of Judge Walter Nixon’s challenge to his impeachment trial by the U.S. Senate was based on Court doctrines regarding ______.

A. political questions B. mootness C. ripeness D. standing to sue E. collusive suits

Criminal Justice

Discuss the Kansas City Patrol Experiment and its impact upon law enforcement

What will be an ideal response?

Criminal Justice