DNA Analysis in Criminal Justice

DNA Analysis in Criminal Justice

Introduction

As a new technology in criminal justice, DNA is reforming the criminal justice system, in that it can help solve crimes with unprecedented accuracy. DNA evidence is based on small samples of genetic material from individuals that are collected at the scene of a crime, tested, and stored, and later used as evidence in court. The tremendous value of DNA evidence resides in the confluence of two factors: that violent crime typically results in the shedding of biological material in the form of blood, semen, saliva, small amounts of skin, or hair; and that DNA found in the cells of these samples holds the unique genetic code of the individual to whom it belongs. Once the DNA is analyzed in a crime laboratory, it can be compared to the DNA of any individual, whether a suspect, victim, or witness. If a genetic concordance (the presence of the same trait) is found during this comparison, a strong inference is formed that the person is the donor of the biological material. The term match is discouraged, as it is misleading. This evidence aids investigators immeasurably in determining what happened during a violent act, and who was involved in it (Frazier, 2000).

DNA evidence is the most reliable and accurate type of evidence that exists today, far more reliable than other types of evidence such as eyewitness identification and confessions. DNA evidence has helped solve crimes as well as exonerate individuals who have been wrongfully convicted. This last use of DNA is helping to reform the criminal justice system by revealing wrongful convictions due to the unreliability of eyewitness identification, coerced confessions, and other, less discriminating forms of physical evidence. However, using DNA evidence also raises some legal and ethical problems that must be addressed in order to uphold the constitutional rights of both defendants and citizens (Heller, 2009).

DNA typing in criminal justice emerged from a history of the use of genetic markers as early as 1900; more recently, the admissibility of DNA evidence has created legal and ethic issues, the problem of post-conviction DNA testing, and arguments for and against DNA database expansion as well as the future of DNA research.

Discussion

Current Legal and Ethical Issues

Problems and questions regarding DNA evidence include individual rights and privacy rights, including those of felons; admissibility of DNA evidence in courts; access to DNA testing post-conviction; use of DNA databases; whose DNA should be in databases; and government surveillance.

Who Should Be in the Database?

Each U.S. state passes legislation enabling the collection of DNA from specific individuals. The criteria for inclusion is typically conviction for a qualifying (serious) felony, but some jurisdictions are expanding the criteria to include those merely arrested and charged with a qualifying felony. In addition, judges sometimes will order an offender included in the DNA database as a condition of probation, even if the underlying conviction is not a qualifying offense.

Other nations around the world are sampling large percentages of their ...