Periodically this season, I've checked in on the raw totals of penalties called by each set of NFL referee crews. This year is my first attempt at tracking such numbers, and when I set out, I wasn't sure whether it would generate anything useful and significant.
Here's what I can tell you as we approach midseason: While most crews have handed out a relatively similar amount of penalties on a per game basis, there is a pretty big gap between the most and least active referees.
The chart breaks down all penalties, both accepted and declined, for each referee this season. Keep in mind that the referees have worked anywhere between one and seven games this season as part of the NFL's rotation system, so perhaps the most significant number is the percentage of penalties per game.
When viewed that way, you'll note the difference between referee John Parry (18.6) and, say, Peter Morelli (11.5) and Clete Blakeman (10.6). But what does that mean?
First, it's important to repeat that penalty totals shouldn't be correlated with the quality of official. Second, it's worth considering that some referees could have been assigned to more games with penalty-prone teams than others.
If that's the case, however, you would expect the numbers to even out over the course of the season. Otherwise, a continuing discrepancy would suggest, in fact, that some referees and their crews were more likely to call penalties than others this season.