3/15 6:35 AM -- Dak Prescott's attorney, Levi McCathern, released a statement on the new investigation ... claiming the accuser and her legal team only filed a police report (in a different jurisdiction) after learning their "extortion plot" failed.

"Doesn’t take a rocket scientist to see what is going on," McCathern said. "Clearly they think that this will somehow mitigate their criminal responsibility for attempting this illegal shakedown."

"It won’t, and it is a true disservice to the real survivors of sexual abuse."

There are now dueling criminal investigations surrounding Dak Prescott and a Texas woman ... with Dallas police launching a probe into sexual assault allegations made against the Cowboys quarterback.

As we previously reported, Dak filed a lawsuit on Monday ... claiming Victoria Shores tried to extort $100 million out of him to not go to police over an alleged encounter that occurred on Feb. 2, 2017.

Prescott and his team have maintained Prescott has never engaged in any nonconsensual acts with anyone in his life ... adding they went to authorities to report Shores' "criminal actions."

TMZ Sports has confirmed the Dallas Police Department received a report on Tuesday of an alleged sexual assault outside the XTC Cabaret strip club on Feb. 2, 2017 ... and the investigation remains ongoing.

Meanwhile, Prosper, Texas officials are investigating Precott's claims ... and the whole back-and-forth will now play out both criminally and civilly.

Cowboys executive vice president Stephen Jones briefly addressed Prescott's status with the team on Thursday ... saying the ongoing situation would not impact his current contract negotiations, but had no further comment considering it is a legal matter.

Prescott is suing Shores and her attorneys for defamation, slander, civil extortion/duress and more.