One of the most commonly known cases of forensic science involves the famous football player O.J. Simpson. This cases shows the importance of forensics inside the lab. 

What Happened?

• ​​On the night of June 12, 1994, Nicole Brown Simpson and friend Ron Goldman, were killed between the time of 10 p.m. and 12 a.m. which took place at Nicole's townhouse.
• Orenthal James (O.J.) Simpson was charged with two counts of first-degree murder. One for the death of his ex-wife Nicole, and one the death Ron.
•  A trail of blood was found at the actual crime scene as well as in O.J. Simpson's house. Blood with DNA matched that of Simpson's at Brown's house. Spots of blood was also discovered of Brown and Goldman in Simpson's car. Genetic fingerprinting was used to match the different samples of blood collected. Gloves and socks of O.J. Simpson contained Nicole's blood on it.
• The three labs LAPD lab, Cellmark (a private lab in Maryland), and the California Department of Justice Lab all conducted that five blood drops leading away form Brown's townhouse matched that of O.J. Simpson.
• Blood smudges were found on the packaging of one of the five blood drops. This indicated that the pieces of cotton (swatches) on which the blood drop had been collected were wet when placed inside their packaging. This may have lead to contamination of the blood sample. 
• It was argued that the swatches might have been switched. One criminalist testified that she placed her initials on the packaging containing the swatches, but no initials were found. Could the water though have erased her initials? Possibly. DNA analyst for the LAPD also contaminated the blood drops found at the crime scene while preparing them for DNA analysis on June 14th, after getting blood from Simpson's voluntarily given sample on his lab gloves.
• Evidence could have been more than deliberately removed and replaced; it was also argued that lab procedures had so thoroughly contaminated the blood evidence that any DNA analysis of the blood would be unreliable. Since the samples were contaminated, all the evidence was useless in convicting O.J. Simpson the murderer. It is controversial if O.J. Simpson was really the criminal?
• Even if the blood drops had been contaminated by lab error, why did the results only show the DNA of O.J. Simpson? This may never be found out. If the collected evidence was never effected then there would be not questioning in the first place and it would easier to convict a criminal. (C.34)