Forensic Challenges: Identifying Fingerprint and DNA on Rough Surfaces

As of 2019, if a person were to apply a fingerprint over another one on a rough surface such as a rock or a brick, they might wonder if it would be impossible to identify the individual. This article explores the complexities and potential solutions in forensic identification, including the challenges of recovering fingerprints from porous and uneven surfaces.

Challenges in Identifying Fingerprints

The question of whether fingerprints can be recovered from a rough surface remains contentious among forensic experts. In the past, it was believed that such surfaces could not yield reliable fingerprints. However, recent advances in forensic science might challenge this conventional wisdom. Even with these advances, the recovery success rate is uncertain, and experts may disagree on the feasibility of the task.

Role of DNA Evidence

Compared to fingerprints, DNA evidence presents a more viable and reliable method for identification. DNA can be found on a wide range of surfaces, including those with fingerprints. However, the recovery and analysis of DNA require a significant amount of resources, which may not be feasible in every case, especially those involving rocks or bricks.

Cost is a major factor in determining the use of DNA evidence. Crime labs often have backlogs due to the high volume of cases, and forensic DNA testing is extremely expensive. Furthermore, the value of recovering a rock or brick in a crime might not justify the expenditure of such resources. In many cases, the amount of loss, such as a broken window and scattered change in a car, is not substantial enough to warrant the investigative measures needed for DNA and fingerprint analysis.

The Role of Surveillance Cameras

Another critical factor in identifying suspects is the presence of surveillance cameras. These devices can capture evidence of a person's presence in and around a crime scene. Even if the cameras only capture the person approaching and leaving the item, this footage can be used to track the suspect back to a known location. By combining video evidence with forensic findings, investigators can build a stronger case.

A significant oversight can be the positioning of cameras near public entry points, such as subway turnstiles. For instance, if someone jumps over a turnstile to avoid detection, precise tracking can be facilitated by analyzing the video footage from the surrounding surveillance systems.

Popular Misconceptions and the Role of Expert Testimony

Many complainants and non-experts believe that fingerprints and DNA can be easily recovered from rocks and bricks. It is essential to recognize that such beliefs are often misguided. The experience of an expert can differ from the experiences of those without professional training. A highly trained forensic expert might be aware of advanced techniques that could potentially recover fingerprints from rough surfaces, but this is not guaranteed.

For instance, a memorable instance involved a complainant's insistence that an expert's knowledge was outdated. The complainant claimed that his uncle, a state trooper, knew better. However, the expert's knowledge remains current and accurate. The common misconception among untrained individuals, often fueled by the media and pop culture, can lead to unrealistic expectations of forensic capabilities.

Conclusion

While fingerprints and DNA are powerful tools in forensic science, their recovery and utility are subject to complex and varying factors. In cases involving rocks and bricks, the practicalities of cost, resource availability, and the value of the evidence often limit the extent of forensic investigations. Surveillance footage and advanced techniques can provide significant insights, but the overarching effectiveness of forensic methods in these scenarios remains a subject of ongoing discussion and research.

For those facing such challenges, it is crucial to understand the limitations of forensic sciences and the value of evidence in criminal investigations. Collaboration between law enforcement agencies, forensic experts, and the public can lead to more effective crime-solving strategies, even in challenging circumstances.