The NFL's report into the Patriots' DeflateGate incident notably hedged when proclaiming the Patriots' guilt. It does not say the Patriots certainly broke the rules. It merely says it "more probable than not" that Pats employees deliberately broke the rules, and that it's "more probable than not" that Tom Brady knew about it.
This is not an example of the NFL wasting five months on an investigation and failing to come to a conclusion. This is not an example of the NFL trying to nail the Patriots when they couldn't find evidence. This is merely an example of the NFL doing what it says it's supposed to do.
The first footnote of the report explains:
The "standard of proof required to find that a violation of the competitive rules has occurred" is a "Preponderance of the Evidence," meaning that "as a whole, the fact sought to be proved is more probable than not."
The report uses the phrase "more probable than not" to describe the Patriots' activities because that is the burden of proof the NFL uses. For someone to be found guilty in criminal court, it has to be proved beyond a reasonable doubt that someone committed a crime. This is not criminal court.
The report didn't say the Patriots certainly committed the crime because it didn't need to. That would be like a grand jury finding somebody guilty of a crime instead of saying there's enough probable cause for them to stand trial.
It turns out the case the report states is rather compelling. The investigators found video evidence of somebody removing the balls from the game room and going into a bathroom with them. Many interviewees stated that it was not incredibly rare for somebody besides referees to abscond with the balls: Text messages from the guy who ran off with the balls to the guy in charge of ball preparation discussing deflation and inflation, Tom Brady's preferences and the report included scientific analysis, stating that it would be essentially impossible for the balls to deflate as much as they did due to temperature, especially considering the Colts' balls did not experience similar deflation in the same conditions.
Basically, the only thing missing from the report is video evidence of McNally deflating the balls. This does not exist because there are, thankfully, not surveillance cameras in bathrooms in NFL stadia. (Or at the least, the NFL is not owning up to their existence at the current moment.)
Is it possible that a) some malicious person trying to frame the Patriots and/or good Samaritan with knowledge of Tom Brady's football preferences got to all 11 balls and deflated them without anybody noticing, b) the Pats employee who went in the bathroom with the balls was having a once-in-a-lifetime brain fart when he walked off with the balls in violation of the standard operating procedure he follows each and every week and c) the text messages between him and the Pats' ball guy about his role as "the deflator" were complete non-sequiturs?
Yes, that incredible coincidence is possible. It is also very, very unlikely. And that's all the report needed to prove.
The report does not say that the Pats are guilty beyond a reasonable doubt because it did not need to. However, if the report did need to find that, it seems like they had enough evidence to do that.
(That all said, we stand by what we wrote in January about how the Pats' punishment for all this should be minor since it's really not that big a deal.)