Which method is most effective for preventing contamination of disk-stored digital evidence?

Using a write blocker is the most effective method for preventing contamination of disk-stored digital evidence. A write blocker is a hardware or software tool that allows read access to a storage device while preventing any write operations. This means that no data can be altered, added, or deleted from the storage medium, preserving the integrity of the evidence.

In digital forensics, maintaining the original state of the digital evidence is crucial for both legal and investigative processes. If any modifications were to occur, it could lead to questions about the authenticity and reliability of the evidence during court proceedings, potentially jeopardizing a case. The write blocker ensures that investigators can access the data and create forensic copies without risking any changes to the original evidence.

Other methods, while they may contribute to overall security, do not specifically address the requirement to prevent contamination of digital evidence as effectively as a write blocker does. For example, a magnetic shield may protect against physical damage or electromagnetic interference but does not prevent data alteration. A data encryption tool secures data but does not prevent it from being written or changed, and a physical lock secures a device against unauthorized access rather than safeguarding the integrity of the data itself.