I haven't read or seen anything to indicate that Tx DPS uses any sort of technology to protect chain-of-custody from tampering by troopers or other parties with

I haven't read or seen anything to indicate that Tx DPS uses any sort of technology to protect chain-of-custody from tampering by troopers or other parties within DPS. This isn't a problem for state prosecutions because a DPS trooper is a sworn officer and is usually considered a reliable witness.