Forensic tools can often recover deleted content, including illegal or pornographic images, from a mobile phone. However, the ability to extract such data depends on various factors, including the specific circumstances surrounding the data deletion, the phone’s operating system, and whether the data has been overwritten.

How Deleted Data Recovery Works

When you “delete” a file on a mobile phone, the system typically removes the reference to the file in the file system, but the actual data remains in storage until it is overwritten by new data. Forensic tools can often retrieve this residual data unless it has been fully overwritten or encrypted.

1. Forensic Imaging: Experts use specialized tools (like Cellebrite, Magnet AXIOM, or XRY) to create a bit-by-bit copy of the phone’s storage. This process captures not only active data but also residual or deleted data.
2. Recovery Techniques:
   • File Carving: Forensic software searches for file signatures in unallocated space (areas of storage marked as free) to reconstruct deleted files.
   • Metadata Analysis: Examines remnants of file system metadata to locate and piece together deleted files.
3. Encryption Challenges: If the phone’s storage is encrypted and the encryption key is inaccessible (e.g., due to a locked phone or user settings), data recovery becomes significantly more difficult or impossible without the key.

Factors Affecting Recovery

• Time Since Deletion: The longer it has been since the data was deleted, the higher the likelihood it has been overwritten by new data.
• Device Activity: Using the phone after deletion increases the risk of overwriting residual data.
• Type of Storage: Modern devices with solid-state drives (SSDs) use a process called “garbage collection,” which may permanently remove deleted data to optimize storage.

Legality and Ethical Considerations

1. Authorization: Accessing someone’s phone and recovering deleted data typically requires proper legal authorization, such as a search warrant.
2. Chain of Custody: Proper handling of the device and documentation of processes are essential to ensure the data is admissible in court and has not been tampered with.
3. Data Sensitivity: Handling illegal or sensitive materials (e.g., child exploitation images) requires adherence to strict legal and ethical guidelines to avoid contaminating the evidence or committing new offenses.

Tools Commonly Used for Recovery

1. Cellebrite: Widely used in law enforcement to extract and analyze data from mobile devices, including deleted content.
2. Magnet AXIOM: A comprehensive forensic tool that can recover and analyze deleted files, metadata, and residual data.
3. Oxygen Forensic Detective: Known for its ability to recover deleted content and analyze complex app data.

Use Cases in Legal Investigations

• Criminal Cases: Recovering illegal photos for evidence in crimes such as child exploitation, human trafficking, or possession of illicit material.
• Corporate Investigations: Identifying misuse of company devices or policy violations.
• Family Law Cases: Providing evidence in custody disputes or restraining order hearings.

Challenges and Limitations

• Data Overwriting: Once data has been overwritten, it is almost impossible to recover.
• Advanced Encryption: Modern devices and apps increasingly use end-to-end encryption, making recovery harder without access to the encryption keys.
• Legal Admissibility: If the forensic process is not properly followed, the recovered data may be challenged in court.

Conclusion

Mobile forensic tools are powerful and can often recover deleted illegal or pornographic images from a phone. However, the process must be conducted by qualified forensic experts to ensure compliance with legal standards and to preserve the integrity and admissibility of the evidence.