The National Football League improperly tried to influence a government research center that was studying the connection between concussions and brain disease, according to a new congressional report released Monday.

The National Institutes of Health does not permit private donors to influence its peer-review research process, but the report from Democratic members of the House Committee on Energy and Commerce said that the NFL rescinded a gift to the NIH for concussion research when it learned the study’s findings would be detrimental to the league’s image. ESPN reports:

The 91-page report describes how the NFL pressured the National Institutes of Health to strip the $16 million project from a prominent Boston University researcher and tried to redirect the money to members of the league’s committee on brain injuries. The study was to have been funded out of a $30 million “unrestricted gift” the NFL gave the NIH in 2012.

After the NIH rebuffed the NFL’s campaign to remove Robert Stern, an expert in neurodegenerative disease who has criticized the league, the NFL backed out of a signed agreement to pay for the study, the report shows. Taxpayers ended up bearing the cost instead.

Research has found that concussions and repeated hits to the head from playing football can lead to chronic traumatic encephalopathy, or CTE. This brain disease has been linked to depression and suicidal thoughts in several former athletes. Deadspin has highlighted several of the major findings in the 91-page report.