Forensic science plays a critical role in supporting criminal investigations and resolving crimes. For example, fingerprints, DNA analysis, and trace evidence from shoes, tires, and gunshot residue can help police identify suspects and establish facts admissible in court.
Fingerprint analysis, for instance, can match a suspect’s print to an impression at the crime scene. Other types of forensic evidence include tool mark analysis and handwriting analysis.
Collecting Evidence
Forensic evidence collection is pivotal in criminal investigations, helping investigators determine suspects’ identities and providing scientific support for legal proceedings. In addition to identifying suspects, forensic evidence allows investigators to corroborate and refute witness statements and provide a more comprehensive picture of the crime scene and surrounding circumstances.
Forensic scientists and crime lab professionals are integral in developing protocols for collecting and preserving evidence and ensuring the process is performed according to scientific standards. Nonetheless, numerous challenges and controversies continue to impact the criminal justice system’s use of forensic evidence. To ensure the reliability of forensic evidence, the criminal justice system must embrace technological advances and address the ethical concerns that arise from those advancements.
DNA Evidence
In some cases, a small sample of DNA is enough to identify a suspect. DNA samples can come from a variety of sources, including hair and fingernails, combs and toothbrushes, cigarette butts, and even food and drink containers.
Other types of forensic evidence include abrasions, latent fingerprints, and trace evidence. The latter can be found on various items, including weapons, clothing, and vehicles. However, the sheer volume of trace evidence can make it challenging to sift through it and identify potential matches. In addition, a lack of adequate training and resources can result in errors during collecting and preserving evidence.
Preserving Evidence
Forensic evidence must be adequately preserved to serve its vital role in the justice system. This requires careful compliance with strict protocols established by the legal and scientific communities.
Protecting the crime scene is one of the most important aspects of preserving evidence. This prevents contamination and ensures that the evidence is in the condition it was in when it was collected. Paying attention to this detail can seriously degrade the credibility of forensic evidence and render it inadmissible in court.
Another crucial aspect of preserving evidence is meticulously documenting the methods used to collect it. This includes the chain of custody, which records who handled and tested the evidence and when. Failure to do so could lead to a lack of reliable information and skewed results in lab tests.
Physical evidence is the most valuable source of information in a criminal case. It can identify suspects, connect them to a crime scene, and provide supporting details that help prosecutors build their case against a defendant. Several high-profile cases have highlighted the importance of ensuring that this evidence is adequately collected and preserved.
Analyzing Evidence
Forensic evidence combines multiple disciplines to analyze physical, biological, and digital data collected at crime scenes. This multifaceted evidence helps to identify suspects, verify timelines, and understand the circumstances of a crime. It can shape criminal investigations, establish guilt or innocence in legal proceedings, and support the pursuit of justice.
The importance of forensic evidence must be balanced. However, the complexities of the crime scene investigation and collecting and preserving evidence can lead to contamination and erroneous interpretations. As such, those in charge of acquiring and analyzing evidence must follow standard operating procedures that ensure the evidence’s integrity.
Physical evidence can be contaminated and degraded in various ways, including by moisture, mold, and chemical substances. To avoid these issues, investigators should systematically search and document the crime scene and package each item of evidence in a sealed bag or envelope with a unique seal number. Additionally, storing all evidence in a cool place, rather than exposing it to sunlight or heat, can help preserve its quality.
Biological evidence, such as blood or semen, can be highly reliable and is an essential tool in identifying suspects or victims.
Testifying
Forensic evidence is crucial to investigative procedures, allowing law enforcement agencies to build an objective narrative supporting criminal proceedings. From corroboration or refutation of witness statements to establishing the identities of suspects and victims, it can also play a significant role in exonerating the innocent or disproving an alibi. In addition, forensic evidence can contribute to the resolution of cold cases and provide a powerful tool for prosecuting suspects who are found guilty.
Forensic evidence collection requires rigorous adherence to legal frameworks and standards, ranging from search and seizure protocols to the admissibility of evidence in court. These governing structures reflect the constant effort to balance law enforcement needs and safeguard individual rights.
As a result, several challenges and controversies stem from using forensic evidence in criminal investigations. For example, backlog issues, which refer to the demand for forensic analysis that exceeds the capacity of crime labs, can hamper the timely resolution of cases. This can be due to limited funding, personnel shortages, and the need to upgrade equipment.
Another challenge is the emergence of new technologies and methods that can create uncertainty about whether or not the evidence collected at the scene is valid. To avoid this, crime laboratories must be able to testify that their processes and results are reliable and valid to support the claim of a conviction.
