When can forensic investigators use decryption methods?

Forensic investigators can use decryption methods when they have legal authorization and the necessary keys. This is essential because decryption processes often involve bypassing security measures that protect data. Without proper authorization, using decryption techniques could violate laws regarding privacy and data protection.

Legal authorization ensures that investigators are following the law and ethical guidelines, maintaining the integrity of the investigation. Additionally, possessing the appropriate keys is crucial for decrypting data; without them, the data remains inaccessible even if the decryption process is employed.

Regarding the other scenarios: utilizing decryption methods at any time during an investigation could lead to legal complications if the necessary permissions are not obtained. Trying to decrypt data only after it has been deleted is impractical, as once data is deleted, the focus would be on recovery rather than decryption. Lastly, decryption is not relevant when dealing with unencrypted data, as such data can be accessed without the need for decryption methods.