To ensure quality and acceptance in legal proceedings, we follow the principles outlined by the Scientific Working Group on Digital Evidence.
- The primary directive of evidence retrieval is procuring and working from the original source recording (or a verified duplicate, preferably digital and uncompressed). Analog sources always incur a loss upon duplication. Digital sources can be exact copies, further verified through metadata.
- Examination and forensic audio analysis includes assessing the technical characteristics of the recording, signal analysis (spectral and dynamic mapping), and outlining the purported recording equipment and original acoustical environment.
- When provenance or audio integrity is in question, authentication seeks to determine if a recording is consistent with the manner in which it is alleged to have been produced. This is best determined by the parties originally involved in the recording process. When this is contested, submitting for further scientific analysis (beyond our scope here) is required.
- Questions often arise about legality of duplications. Any duplicates made in my custody will be exact copies with no loss of signal or metadata. Note that “A duplicate is admissible to the same extent as an original unless (1) a genuine question is raised as to the authenticity of the original or (2) in the circumstances it would be unfair to admit the duplicate in lieu of the original.” [Federal Rule of Evidence 1003]
- Acceptance. Most courts use some version of the "fair and accurate representation" standard as a measure of acceptance of audio recordings. The same general principles apply regardless of the format in which the audio is recorded and the physical media onto which the recording is stored.
- Handling evidence requires documentation of every step of the process, including communications, shipping records, media condition, media hash values, and my working methods. You receive a full report including chain of custody.
- The steps taken in the critical forensic audio repair & recovery phase occur in a 100% digital environment using industry-standard sound restoration software. When necessary, vintage media transfers are outsourced to skilled personnel whose processes are completely documented.
- Delivery occurs in an uncompressed, high-quality media format unless requested otherwise. The client may specify instant online transfer, physical write-once media, or another method. All clients receive a complete report of forensic audio services including metadata analysis and chain of custody.