# Why Tom Brady may have a strong case for a lawsuit against the NFL

If a new study from the American Enterprise Institute is correct, the Patriots and their quarterback Tom Brady are going to sue the NFL for defamation in the so-called “Deflate gate” scandal.  The accusation that the Patriots had broken the rules during their playoff game earlier this year with the Indianapolis Colts permanently tarnished Tom Brady’s stellar football career, but it looks as the NFL hid importance evidence and misinterpreted what they did report.

Brady not only looks set to win his appeal of the NFL’s four game suspension, but he has a good chance to win a defamation suit against the league.

The NFL’s evidence against the Patriots seemed straightforward: when referees measured the air pressure at halftime, the eleven Patriot footballs had experienced a significantly larger air pressure drop than the four Colts balls that were measured.  Before the game, the referee had measured the air pressure in the footballs at 12.5 PSI (pounds per square inch) for the Patriots and 13.1 PSI for the Colts.  At half time, the Patriots had fallen to 11.3 PSI but only down to 12.53 for the Colts.

The difference was statistically significant.  The pressure in the Patriot balls had fallen by more than those for the Colts.  Case closed, right?  Not so fast.

Tom Brady not only looks set to win his appeal of the NFL’s four game suspension, but he has a good chance to win a defamation suit against the league.

Not surprisingly for a game played in mid-January in Foxborough, Massachusetts, the temperature on the field was a frigid 20 degrees Fahrenheit. And cold temperatures cause the air pressure in the footballs to fa;;.  From physics, the “Ideal Gas Law” predicts that the air pressure in the Patriots’ balls should have fallen to about 11.3 to 11.5 PSI and for the Colts, whose balls started out at a higher level, down to 11.8 to 12.0 PSI.

The pressure in the Patriots’ balls had fallen the exact amount that they were predicted.  The puzzle is why the four Colts’ balls fell by less than they should have.  The answer turns out to be very simple.  After the balls were brought inside during half time, the Patriots’ balls were tested first.  They had little time to warm up.  By contrast, the Colts’ balls were only tested after being indoors for about 15 minutes, almost the entire duration of half time.  Indeed, the reason that only four of the Colts’ balls were tested is that the referee waited so long to test them that he only had time to test four.

Unfortunately, the American Enterprise Institute scholars found the NFL had excluded important information from their report. For example, there were two different gauges used to measure the balls’ air pressure, and the NFL report conveniently discounted the referee’s claim that the gauge used to measure pressures before the game was the one giving a pressure reading that was 0.4 PSI higher than the other gauge.  The NFL claims that either gauge wouldn’t alter their findings.

But the NFL didn’t actually test that possibility.  If the referee is correct, while there is still a greater drop in air pressure for the Patriots’ balls, the difference with the Colts’ balls is no longer statistically significant.

In addition, the NFL didn’t include the PSI measurement for a Patriots’ ball that had been intercepted by the Colts.  This ball had a PSI of 11.55, at the top of the range predicted by the Ideal Gas Law, and was excluded from the NFL’s statistical tests.

For two of the authors on the American Enterprise Institute study, Kevin Hassett and Stan Veuger, this isn’t the first time that they have waded into football controversies.  When the New Orleans Saints were allegedly paid to injure the players on other teams, the so-called “bounty scandal,” Hassett and Veuger looked at the actual injury rate for players on opposing teams. They found that the New Orleans Saints’ players actually injured fewer competing players than all but one team during 2009, the alleged first year of their bounty program, and that there was no evidence that Saints injured more players than the average team over the three years that the bounties were supposedly in place.  Hassett and Veuger’s evidence carried the day in that case.

Public figures can only really sue for defamation when someone knowingly presents false claims.  That is a very difficult standard and few public figures can ever successfully sue for even the most outrageously false claims.  But while some of the mistakes in the NFL report might well be due to simple incompetence, the failure to report exculpatory evidence -- such as the referee’s statements on which pressure gauge was used before the game -- raise concern about intent. The NFL could face real headaches in any lawsuit brought by Tom Brady.