It has recently been pointed out to me that there is a basis for a traffic stop that does nto require reasonable suspicion or probable cause.
Transportation Code Section 521.025(b) says:

"A peace officer may stop and detain a person opreating a motor vehicle to determine if the person has a driver's license as required by this section".

Perhaps officer's should be made aware of this section so they can consider it in the future as a basis for their traffic stops? Am I misreading this?

Richard, I found this section about a year ago and thought I had found the Holy Grail. After researching the annotations, it appears we do not get to make use of it like you are thinking even thought the clear language of the statute seems to imply we can.

Might not there be some constitutional concerns about detaining someone without reasonable suspicion that an offense is being committed? Wasn't that one of the concerns about roadblocks? Just thinking out loud.

I believe that the U.S. Supreme Court's decision in Delaware v. Prouse renders that particular statute provision useless. The court heldthat when an officer stops a automobile and detains the driver in order to check the driver's DL and the vehicle's registration, it constitutes an unreasonable seizure under the Fourth Amendment if there is no articulable reasonable suspicion that the driver is unlicensed or the vehicle unregistered, or there is no other legal basis for the seizure.

So re: our over-zealous game warden who stops vehicles seen leaving fishing and hunting areas to "check for licenses and measure their fish", but who is really looking for DWI's.... Can I use this case to defer prosecution for lack of reasonable suspicion to stop?

What about Schenekl v. State, 30 S.W.3d 412 (Tex. Crim. App. 2000)? The statute in question there allows game wardens to stop boats without suspicion and conduct "water safety checks." The CCA held that the statute was constitutional and upheld the conviction for boating while intoxicated. The CCA distinguished Prouse. While Prouse is right on point as to the driver's license situation, the game warden situation might be different if the statute he is relying on is as narrow as the water safety statute.