Crime Scene Investigation Methods, Research Paper Example


Crime scene investigation is an evolving part of the criminal justice system, and the types of evidence accepted by the legal system changes as science develops. The below paper is designed to thoroughly investigate the current and past evidence collection methods and compare their effectiveness based on conviction rate and reliability.

From the evolution of fingerprint investigation, forensic science has gone a long way. The developments of technology available today are all designed to ensure the increase of correct conviction rates and to eliminate sources of errors in the criminal justice system. While collecting, storing and providing evidence for the legal system is highly regulated, there are specific, fast-evolving methods that are able to help prosecutors do their job more effectively today and in the near future. The below paper is going to investigate these methods of evidence collection and the opportunities they provide for the legal system, compared to past methods.

Thesis Statement: While there are various emerging forensic methods available for the criminal justice system, the lack of regulation creates an atmosphere of mistrust, therefore, there is an urgent need for federal legislation of the industry.

Types of Evidence

There are different types of evidence accepted by the court in criminal cases; trace evidence, direct evidence and circumstantial evidence. Evidence, especially biometric type of sample can also be divided into two groups; class evidence and individual evidence. This categorization basically determines how direct or reliable the evidence is. For example; a DNA match is almost a hundred percent reliable and is considered individual, while blood type is a class evidence. (Nuffield Council on Bioethics, 2007)

Obviously, information technology has impacted criminal evidence collection and processing procedures in the past two decades as well. Ami-Narh and Williams (2008) analyzed the impact of evolving computer science use in forensic evidence collection and processing, as well as its legal implications. The authors confirm that the vulnerability of computer systems creates a great challenge in forensic science and an obstacle for the legal system to fully accept these types of data. The regulatory and policy requirements of digital forensics will be examined further in another chapter of the paper.

Recent Innovations in Crime Scene Investigation

According to Buckles (2007), there are various accepted innovations in forensic science that provide extra information for investigation purposes. From alternate light sources making the detection of fingerprints and body fluid easier to lasers that are able to determine the source and route/angle of the bullet, electrostatic lifting of fingerprints and GPS; many systems were developed in order to increase the reliability of physical evidence in court.

Electronic evidence, on the other hand, involves further regulations and as the reliability of systems is often questionable, it is important that there are adequate procedures and policies in place regarding collecting, storing and processing the information. First responders need to be aware of their responsibilities regarding the “recognition, collection, preservation, transportation and storage of electronic evidence. (Ashcroft, 2001)

Jain and Kumar (2010) reviewed biometric approaches to forensic science. While detailing the future systems, they also highlight the main existing guidelines in place. The two main traits of biometric evidence recognition, according to the authors should be based on distinctiveness and permanence. The use of fingerprint analysis has been around for decades, however, iris recognition is just emerging. The most commonly used biometric traits for identification are fingerprints, face, iris, palm print, hand shape, ear, retina and signature.

The Future

Buckles (2007) depicts a bright but confusing future of crime scene investigation and criminal science. By the constant improvements of technologies and tools, the processes are likely to become simpler, faster and more reliable. By creating better imaging and visualization, latent prints can be retrieved more effectively. Photogrammetry is a method that makes creating maps and sketches easier and more accurate. Different measuring methods, such as advance distance measuring devices can become effective 3D visualization tools. Buckles (2007) also mentions miniaturization, lab-on chip using nanotechnology in the forensic laboratories, gas chromatograph and microchip blood analysis. In the future, DNA can easily be stored on a chip, making data smaller, processing faster and results more reliable. (p. 278.) Automation combined with data mining would make evidence documentation more effective and faster. Teleforensics and thermal images are also developing fast and can help in hostage situations to determine where suspects or hostages are located within the building. Robotic technology still has a long way to go, however, once the technology is in place, the cost or processing evidence could be reduced while the process can be shortened.

DNA is the fastest evolving forensic identification method, and it was first used in court during the Orlando Cases in 1986 when a series of rapes occurred in a short period of time. The suspect, Andrews was finally convicted based on the DNA match, as all the other evidence was class-type and not individual. (Swanson et al. 2011) Swanson et al also mention biometrics as an emerging field. It helps forensics through facial and voice recognition, iris analysis, odor. However, the authors state that some of these methods are questionable, as iris might be affected by aging, alcohol, drugs or hormone levels. Magnetic resonance imaging (MRI) of the brain can provide a more reliable lie detection than the current ones.

Regulatory Issues

Buckles (2007, p. 281.) confirms that current forensic laboratories are not closely monitored or regulated. While there is an accreditation in place called Crime Laboratory

Accreditation Program, it is not compulsory. Only about half of the labs in the United States are accredited, and fact might undermine the credibility of the field within the legal system. Self-regulation is also based on individual policies and internal measures. The author calls for standardized testing and guidelines issued by the government that would ensure adequate quality control is in place. Ami-Narh and Williams (2008) cover the connection between computer forensics and the legal system. The authors determine six different forensic investigation processes: identification, search and seizure, preservation, examination, analysis and reporting. In order to seize computers or digital evidence, there is a need for a search warrant. Several guidelines and measures need to be put in place in order to ensure the evidence is sealed and not tampered with in any way. As digital evidence can be accessed and altered without traces, the legal system is taking extra care regarding the acceptance of these types of data in court. Describing the legal framework the authors emphasize the importance of documentation and data integrity protection.

The Attorney General’s guidelines (Ashcroft, 2001) recommend measures for first responders in criminal cases regarding electronic crime scene investigation. The Attorney general highlights the importance of handling electronic evidence with care, due to its fragile nature. (p. 1.) He states that “Actions that have the potential to alter, damage, or destroy original evidence may be closely scrutinized by the courts.” (p. 1.)

The guidelines relate to collecting, documenting and transporting digital evidence, as well as recommend the collection of non-electronic evidence at the same time; such as fingerprints and written passwords. Packaging and storage procedures are also covered by the document, and the guidelines are giving clear instructions for first responders in order to increase the digital evidence acceptance rate by courts. The guideline document determines three main crime types in which digital evidence can have a high importance: sex crimes, crimes against persons and fraud or other financial criminal activities, including auction scams and identity theft.

Technology and Issues Regarding Evidence Reliability

While technology is constantly improving, as it has been determined in the previous chapters, the regulations need to match the legal requirements. Privacy guidelines and legislation have to be considered and anti-tempering measures have to be put in place. As Jain and Kumar (2010) confirm, biometric evidence collection  is often considered invasive, while a biometric system is prone to errors. Performance needs to be measured and kept at a high standard in order to create evidence credibility. Likewise, the current costs of software and laboratory equipment is high, and as equipment measures, technologies change on a regular basis, the maintenance of the equipment, keeping applications secure and up to date is costly. The authors recommend the application of an interchangeable system that allows fast and effective, error-free data exchange even between laboratories in different geographical locations. However, security is one of the main concerns regarding biometric systems. They are extremely vulnerable to spoof and malicious attacks. Therefore, in order to ensure the accuracy of biometric evidence, adequate security platforms and access control protocols need to be put in place.

Comparison of Past and Emerging Methods

From the above review of forensic evidence collection methods, it is evident that the industry is moving towards individual evidence and uses computer science combined with biometric analysis. However, both of the emerging methods are currently developing and not adequately regulated to be widely accepted. The risk of tampering in case of both types of evidence is high, while the costs of running forensic laboratories and providing data security is high.

Fingerprinting has evolved through the use of LIVESCAN and mobile fingerprinting devices, and it is now possible to lift fingerprints from more objects than before. Digital fingerprint recognition systems can speed up the process of evidence and provide faster results, identifying suspects before they would have a chance to escape. The collection of biological samples for DNA profiling helps forensic science create an individual evidence. DNA fingerprinting has helped in several cases to identify suspects.

The  National Research Council (2011) confirms the most important sources of bias regarding emerging forensic evidence collection methods. These include human judgment, questioning, reasoning and conclusions drawn from the evidence. That means that strengthening the presence of individual evidence in court would be extremely important, while reducing the number of circumstantial and class evidence would provide a lower error rate in the legal system and more correct convictions.

Regarding biological evidence, science has more tools in hand than ever before to gain relevant information as soon as possible. DNA can now be retrieved from body fluids, and instead of determining blood type, a DNA fingerprint can be created and submitted as evidence. However, the testing of DNA samples involves a series of analyses in the forensic laboratory. (National Research Council, 2011). The current process involves the entering of results into the “Federal Bureau of Investigation’s (FBI’s) Combined DNA Indexing System (CODIS) and are searched against DNA profiles already in one of three databases. (National Research Council, 2011 p. 131.) In some cases, however, degraded DNA is present and the profiling is not possible, and the question is whether the legal system should consider these types of samples as valid evidence.

Chemical analysis through computer systems is a new process that helps the criminal justice system identify illicit drugs and substances. The identification and analysis of these samples a few decades ago took weeks or even months, however, with the help of computer technology, now results can be obtained quickly. Documentation and the lack of regulation has caused fraction between criminal science and the legal system before. The National Research Council (2011 p. 143.) details two different cases: New Hampshire vs. Richard Langill and Maryland vs. Bryan Rose, in which latent print retrieval was not correctly documented. Error rate of computerized systems can create a lack of credibility in the legal system, and the author also calls for uniqueness and persistence, just like Ami-Narh and Williams (2008). The The National Research Council (2011) lists some recommendations for forensic analysts and first responders in order to increase the credibility and accuracy of the latest evidence analysis methods. Also, the document calls for the integrated governance of the forensic science community, which would also include guidelines of operation for laboratories. According to the document, “Law enforcement agencies within the United States vary in organizational structure regarding how forensic science examinations are conducted and evidence is admitted into court”. (National Research Council, 2011 p. 55.) Standardization might be the solution that would benefit forensic scientists, first responders, legal system workers and those involved in the criminal justice system directly or indirectly alike. However, standardization and regulation has several obstacles: first of all; legal systems and criminal justice specifics vary from one state to another. Secondly, the accepted types of evidence do vary from one court to another. Third, processing evidence involves different software and hardware in every laboratory, and data is currently not interchangeable. Further, laboratories vary based on funding, jurisdiction and structure. (p. 57.) Training and expertise levels also vary between laboratories.


            While the above research has covered the emerging forensic evidence collection and analysis systems and the opportunities they provide for prosecutors and the criminal justice system, various obstacles have been identified in the way of development and process improvement. While the criminal justice system is moving towards a preference of individual evidence instead of circumstantial and class evidence, the regulation and standardization of the area is still awaited. While processes, regulations and guidelines differ between states and various jurisdiction entities handle DNA, computerized and digital evidence differently, there is no real hope for increasing the credibility of the newly emerged forensic methods. While regulation, process and quality improvement programs would require financial resources and government funding, they would provide more reliable and usable data for the criminal justice system long term. The above examined National Research Council (2011) document provides adequate guidance for government agencies on creating federal policies and guidelines for evaluating and accrediting forensic laboratories. After these measures are in place, the new methods can gain traction in the federal and state criminal justice system, providing more reliable evidence for prosecutors, making the court’s processes simpler and faster.


Buckles, Thomas (2007). Crime scene investigation, criminalistics, and the law. Clifton Park, New York. Delmar

Swanson, C., Chamelin, N., Territo, L., Taylor, R. (2011) Criminal investigation. McGraw-Hill. Chapter One.

Ami-Narh, J., Williams, P. (2008) Digital forensics and the legal system: A dilemma of our times. Australian Digital Forensics Conference. Edith Cowan University Research Online.

Strengthening Forensic science in the United States: A path forward. National Academy of Sciences. Committee on Identifying the Needs of the Forensic Sciences Community, National Research Council. 2011. Web.

The Forensic Use of Bioinformation: Ethical Issues. Nuffield Council on Bioethics. 2011. Web.