How can digital evidence be collected and analyzed without tampering?

1 The importance of digital forensics

Digital forensics is a multidisciplinary field that combines computer science, law, and investigation. It aims to answer questions such as who, what, when, where, how, and why in relation to digital evidence. Digital forensics can help solve crimes, prevent fraud, protect intellectual property, enforce policies, and support legal claims. However, digital forensics also faces many challenges, such as the diversity and complexity of digital devices and systems, the large and volatile nature of digital data, the encryption and obfuscation of digital evidence, and the ethical and legal implications of accessing and handling digital evidence.

2 The principles of digital forensics

Digital forensics must adhere to certain principles in order to guarantee that digital evidence is reliable and admissible in court. The principle of legality requires that digital forensics comply with the applicable laws and regulations of the jurisdiction where the evidence is located and where the case is tried. Preservation of evidence is also essential, as it ensures that the original state and condition of the evidence is protected and any unauthorized or accidental changes are prevented. Furthermore, documentation of every step taken during evidence collection and analysis must be recorded, including date, time, location, personnel, tools, methods, results, and chain of custody. Verification of accuracy and validity of evidence and tools used is also necessary through techniques such as hashing, checksums, signatures, and peer reviews. Finally, digital forensics must be conducted in an impartial manner without any preconceptions or influences.

3 The phases of digital forensics

Digital forensics typically involves four main phases: identification, acquisition, examination, and reporting. Each phase has its own goals, methods, and challenges that require thorough understanding of the scenario, devices and systems involved, as well as legal authority and scope of the investigation. For example, the identification phase requires careful planning and preparation of resources, tools, and procedures for the next phases. The acquisition phase involves collecting digital evidence from the original sources to a secure environment using techniques such as write blockers, imaging tools, encryption tools, and anti-virus tools. Additionally, it requires verification and documentation of the evidence using techniques such as hashing, checksums, signatures and logs. The examination phase involves analyzing and extracting relevant information from the digital evidence with the selection and application of suitable tools. It also requires verification and documentation of analysis with hashing, checksums, signatures and reports. Finally, the reporting phase involves presenting findings to the intended audience with proper organization and synthesis of information using tables, charts, graphs, screenshots and summaries. It also requires proper explanation and interpretation of evidence using logic reasoning evidence and arguments.

4 The challenges of digital forensics

Digital forensics is a complex process, facing several challenges that can impact the quality and validity of digital evidence. For instance, the diversity and complexity of digital devices and systems, the large and volatile nature of digital data, the encryption and obfuscation of digital evidence, as well as ethical and legal implications when accessing and handling digital evidence, can all make the collection, analysis, acquisition, examination, identification, extraction, and investigation more difficult. Digital evidence can come from various sources such as computers, smartphones, tablets, cameras, GPS, IoT, cloud, social media and more. It can also be massive in size due to big data or multimedia. Furthermore, it can be protected or hidden using techniques such as encryption or steganography. Moreover, it can contain sensitive or personal information that needs to be handled with care to avoid ethical or legal issues.

5 The best practices of digital forensics

To ensure the quality and validity of digital evidence, digital forensics should follow some best practices, such as planning and preparing for the collection and analysis of evidence by defining objectives and resources, handling and preserving the evidence by minimizing physical and logical damage, selecting and applying suitable tools and methods, and organizing and synthesizing the information extracted from the evidence. These best practices involve obtaining necessary legal authority, using write blockers, imaging tools, encryption tools, anti-virus tools, hashing, checksums, signatures, logs, tables, charts, graphs, screenshots, summaries, logic, reasoning, evidence, arguments, and presenting findings to the intended audience.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?