GTL, FTR, and Other Proprietary Audio Formats: A Lawyer’s Survival Guide
The format wall
Sooner or later a disc or download link arrives that your computer cannot open: jail calls wrapped in a vendor’s player, court audio in a format nothing recognizes, or a folder of files with extensions you have never seen. The evidence is in there. The practice of law should not require a degree in audio codecs, but a working map of the common formats saves real time.
The common offenders
- GTL and ViaPath jail calls usually export as ordinary WAV or MP3 files, sometimes wrapped in a branded player on the disc. The audio files themselves generally play anywhere; look past the player.
- Older facility exports sometimes use WMA or other aging formats. These convert cleanly with standard tools.
- FTR court recordings are the genuinely closed case: the .trm format needs FTR’s own player, which exports to WAV. Install the free FTR Player, export, and work from the export.
- Dashcam and interview room audio sometimes arrives inside video containers; the audio track extracts without loss.
Converting without altering the evidence
Conversion for review is routine and defensible when the original is preserved. What you want to avoid is editing in place, renaming originals, or re-compressing audio you may later need to enhance. A disciplined folder structure, originals in one place and working copies in another, costs nothing and settles arguments before they start.
When review software absorbs the problem
A review platform that accepts common audio formats directly removes most of the wall: upload the WAV or MP3 exports from the jail call production and the transcripts come back without a conversion step. For the true holdouts like FTR, the free-player export path remains, and the exported WAV uploads like anything else. The goal is that no piece of evidence goes unreviewed because of its wrapper.
The five-minute checklist
- Inventory the production: list every file and extension before opening anything.
- Try plain playback first; more of these files are ordinary audio than the packaging suggests.
- For a vendor player, look for the raw audio files on the same disc or in the same folder.
- For FTR, install the free player and export WAV copies.
- Preserve originals untouched, and review from copies.