Brett Favre in Fed's Crosshairs After Ex-Miss. Welfare Agency Head's Guilty Plea

Brett Favre's alleged involvement in a multi-million dollar welfare scandal may have just gone from bad to worse ... 'cause a key figure in a criminal case has just made a deal to cooperate with the feds that could put the NFL legend in the crosshairs of the Justice Department.

Former Mississippi Department of Human Services director John Davis pled guilty on Thursday to conspiring to defraud the State of Mississippi out of more than $70 million in federal funds, which he was accused of misdirecting from the state's poorest people.

As part of his agreement with prosecutors, officials say Davis agreed to tell everything he knows about the massive scheme ... which could be problematic for Favre.

The former Green Bay QB has been under fire after he allegedly worked with Davis and other government officials to obtain $5 million from Mississippi welfare funds to help his alma mater, the Univ. of Southern Miss., build a new volleyball facility. Favre's daughter played the sport at the Univ. at the time Favre was accused of getting the money for the project.

Favre sent a text in 2017 to the woman who ran the nonprofit, seemingly acknowledging it was wrong to take the money ... "If you were to pay me is there any way the media can find out where it came from and how much?"  She responded, "No we never have had that information publicized."

A few hours later, the woman who runs the nonprofit texted Favre back, saying "Wow, just got off the phone with [then Mississippi Governor] Phil Bryant! He is on board with us! We will get this done!" Favre responded, "Awesome. I needed to hear that for sure."

Despite facing 15 years behind bars, Davis is being seen as an essential component in the ongoing federal investigation into the misdirection of the funds, as well as a corresponding state case. Prosecutors on both sides are eager to obtain information on other possible co-conspirators, including those connected to Davis.