A.J. Perez

USA TODAY Sports

A congressional investigation claims NFL officials “improperly attempted to influence the grant selection process” in a concussion study led by the National Institutes of Health (NIH), according to a report released on Monday.

The investigation was launched after ESPN reported in December that the NFL, which had promised as much $30 million for the study of the debilitating brain disease chronic traumatic encephalopathy (CTE), withheld funding from the NIH due to the involvement of researchers from Boston University.

“The NFL’s interactions with NIH and approach to funding the BU study fit a longstanding pattern of attempts to influence the scientific understanding of the consequences of repeated head trauma,” the report released by the Democratic members of the House Committee on Energy and Commerce states. “These efforts date back to the formation of the NFL’s now-discredited (Mild Traumatic Brain Injury) Committee, which attempted to control the scientific narrative around concussions in the 1990s.”

The NFL said it "rejects the allegations" laid out in the report, according to a statement provided to USA TODAY Sports.

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The NFL had promised millions in 2012 to the NIH through the Foundation for NIH (FNIH), a nonprofit set up to facilitate funding to the NIH from the private sector. Such funding isn’t supposed to alter how grants are issued, something the report alleged occurred as the NFL voiced misgivings of funding the project led by Boston University, which has diagnosed CTE in the brains of dozens of former NFL players.

“This investigation confirms the NFL inappropriately attempted to use its unrestricted gift as leverage to steer funding away from one of its critics,” Energy and Commerce Ranking Member Frank Pallone (D-NJ) said in statement. “Since its research agreement with NIH was clear that it could not weigh in on the grant selection process, the NFL should never have tried to influence that process.”

The NFL denied it pulled funding because the BU study was selected by NIH. The FNIH said in a statement in December that it was the NIH's decision to fund concussion research without the NFL's money.

Here's the full statement from the NFL:

"The NFL rejects the allegations laid out in the Democratic Staff Report of the House Committee on Energy and Commerce Committee.

"There is no dispute that there were concerns raised about both the nature of the study in question and possible conflicts of interest. These concerns were raised for review and consideration through the appropriate channels. Ultimately the funding decision was made by the FNIH/NIH, not the NFL, as the FNIH's public statement of December 22, 2015 confirms. The nature of those conversations and a detailed account of the concerns were communicated in full to the committee members. It is deeply disappointing the authors of the Staff Report would make allegations directed at doctors affiliated with the NFL Head, Neck and Spine Committee without ever speaking to them.

"In 2012, the NFL committed $30 million to the NIH to advance the diagnosis, prevention, and treatment of head injuries. To date, $12 million has been allocated for pathology studies through the Sports and Health Research Program (SHRP), two $6-million cooperative agreements dedicated to defining the long-term changes that occur in the brain after a head injury or multiple concussions: Boston University School of Medicine and U.S. Department of Veterans Affairs received $6 million for a study on CTE and post-traumatic neurodegeneration, and Mount Sinai Hospital received $6 million for a study the neuropathology of CTE and Delayed Effects of TBI.

"The NFL is deeply committed to continuing to accelerate scientific research and advancements in this critical area, and we stand ready to support additional independent research to that end."

READ: Report on NFL/NIH investigation