Watching the Clock. Although it's a group descended from the DTI, not the DTI itself. I can't remember if we were ever told their 31st century name, but by the 29th century, policing of the timeline is done by a Starfleet subsiduary called the Temporal Integrity Commission. Daniels wasn't a part of Starfleet, so things have changed again in the intervening 200 years (thats even IF the 29th and 31st century time cops represent the same version of the future. A line in Watching the Clock suggested that they weren't entirely sure themselves.
Wasn't it suggested the 31st century temporal agents were a civilian group, which Ducane disapproved of.