Team Penalty Statistics
By Matt Femrite
It’s pretty common during games for broadcasters and other bright basketball minds to explain how getting teams in the penalty early is a big deal. This is because after either committing four team fouls[1. One less foul is allowed in overtime.] or one within the final two minutes of a quarter, every other team foul results in two free throws, and free throws are the most efficient way to score in basketball. If Golden State is up by a few possessions with 10 minutes left in the fourth quarter and has their opponent is already in the penalty, the game is pretty much over, right?
The problem for so long has been that we don’t really know how much having the defense in the penalty helps. Box scores show stats like points off turnovers and points in the paint, but there’s nothing related to the penalty. That’s odd when it has seemed like such an important part of the game with the way it’s talked about, and it should be just as easy to tally. Broadcasts keep track, usually showing when teams are in the penalty below their scoreboard which is nice, but they’re sometimes a foul late, displayed after the fifth team foul of the quarter or second in the final two minutes.[1. I feel like this has been better this season, at least.] NBA.com has team fouls in their play-by-play data, also nice, but there are no penalty stats to be found on the site. Out of curiosity and a little frustration, I’ve been keeping tabs on penalty splits this season.
82games.com was something of a guide, publishing the only related post I’ve come across that split up efficiency and other stats by foul situations. I haven’t tracked every team foul like they had done, though, instead splitting team production just by when teams were and were not in the penalty. In the case of a shooting foul that put the defense in the penalty, I treated those attempts and points as not in the penalty. In the case that a missed free throw from that shot foul led to an offensive rebound, I treated whatever happened after that, whether it was a shot, more free throws or a turnover, as its own separate possession.
So let’s take a look at some results so far. As a reminder we are only two weeks into the season, so team-by-team numbers are still unusual. League-wide, though, we had exactly 19,000 possessions to look at going into Monday night’s games, which won’t be a lot by the time we look back in April at these results, but it’s still something. Just how big has the average difference been so far between teams in the penalty and when they have not been in the penalty?
A five-point difference for all quarters seems underwhelming. Compared to 2004-05, however, it is only half as large. 82games found that the difference in offensive efficiency between in the penalty and not in the penalty back then was seven to ten points per 100 possessions, depending on the team foul total prior to the penalty. Even then, seven to ten points might not be as high of a difference as expected, and certainly not the two-point difference in quarters two and three. The increase in free throw rate is consistent with what 82games found as well as the decrease in turnovers per 100 possessions. There’s also an increase in three-point rate, but a small decrease in shooting percentage.
Some of this is probably team-dependent or just whenever Stephen Curry decides to shoot. Despite the small sample so far, let’s take a look at how long each team has spent scoring and defending in the penalty anyway, as well as their efficiency in each situation. Stats were before Monday night’s games:
A small sample worth noting so far could be the Boston Celtics, currently having the biggest difference on both offense and defense, the worst offense when not benefiting from the penalty, and the stingiest defense when they have fouls to give. Denver and Dallas lead the 10 teams currently scoring less efficiently with the penalty on their side, currently 15 points per 100 possessions worse than their non-penalty rate while Denver leads the nine defenses that defend better when in the penalty with a similar difference to Denver and Dallas’s offense. Going over each team doesn’t feel too productive right now, though, as we’re only two weeks into the season. In time, we’ll see how the penalty impacts defenses that are more physical and if the Houston Rockets and Sacramento Kings, the top two teams in free throw rate last year, have noticeable differences in their scoring.
This was all meant to be an introduction anyway. With more games and possessions, more can be explored. It wouldn’t be surprising if players like LeBron James and James Harden have different tendencies when in the penalty. DeMarcus Cousins, a foul-drawing machine, would also be worth looking at.
Until then, hope this introduction helped. You can find team stats at the bottom of our Team and Rating Statistics page.
Statistics were from NBA.com’s play-by-play data and Darryl Blackport‘s possession totals.