On Oct. 12, Rep. John Conyers, D-Mich., chairman of the House Judiciary Committee, and his colleagues on that committee wrote to Goodell and Upshaw, formally requesting information to prepare a bipartisan Congressional Research Service (CRS) report. According to the committee's letter, the CRS report will provide "an objective analysis of the types and severity of injuries suffered by NFL players, the benefits programs available to injured players, and the barriers to former players seeking benefits."
"In addition," the letter stated, "the report will delve into related issues such as the problem of concussion and its long-term effects on players."
"We do not know how many players end their careers because of injury," the NFL stated in its written responses to the House Judiciary Committee. "Players retire for many reasons; because they do not make the team, because they wish to start their second career, because they lose the desire to play, or because they wish to spend more time with their families. No records are kept regarding the reasons that players retire."
The NFL released that portion of its response to ESPN.com this week.
"The data concerning injuries and what does or does not cause a player to leave the game of football is not tracked by the NFLPA," a spokesperson for the players' association told ESPN.com.
The judiciary committee expects the CRS report to be completed by the end of the year.
The NFL and NFLPA took until Nov. 5, 10 days beyond the committee's original deadline, to answer the congressional queries. The league and players' association both declined to make the bulk of their responses public. Conyers has not yet determined whether or when his committee will release the documents.
But neither the league nor the union could respond to all of the questions the committee posed. The sixth of 32 questions sent to the NFLPA asked, "How many players have retired because of an injury or injuries? What types of injuries did these players sustain?" The seventh of 11 questions sent to the NFL had almost identical wording. And neither the NFL nor the NFLPA knew the answers.
Asked this week about disabling injuries, the union suggested it is the league's job to track the reasons players retire.
"Perhaps you should ask the NFL this question -- or each team individually," an NFLPA spokesperson told ESPN.com.
Meanwhile, the NFL said it is difficult to determine why players leave the game.
"Other reasons players retire would be declining skill, the team has decided to go younger, the team says it will no longer pay the player at that level for cap reasons and the player decides it's time to hang it up," Aiello told ESPN.com. "In all those cases, an older player like that may also have some injuries from his long career. Did he retire 'due to injury'?"
Former Vikings guard Brent Boyd, shown testifying here in September, is a vocal critic of the current Retirement Board. As members of Congress probe the rest of the responses, they are particularly concerned about the lack of representation former players have in the league's benefits process.
"Right now, we're seeing so many claims rejected that it raises questions," Sanchez said. "This is my concern: Is it something that's systematic, to discourage, harass and utterly defeat these retirees? Let's face it, after years of going through the process, you wonder if it's worth it."