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23 Dec 2003

Are Penalties Overrated?

by Michael David Smith

It defies everything every coach and commentator says, not to mention common sense. I can't explain it, but I can't ignore it either.  There is no correlation between a team's penalties and its won-loss record.

This phenomenon was first noted in The Hidden Game of Football. But its authors, Bob Carroll, Pete Palmer and John Thorn, while uncovering the surprising piece of information, also made a key error in describing it. The authors wrote, "[Penalties] don't make a whole lot of difference. Over the course of a season, they tend to even out. For every drive-killing holding penalty, there's an interference call that keeps a drive going."

The truth is, penalties don't even out. Looking at the whole of last season, it's clear that some teams were consistently penalized more than other teams. The difference is equal to a few hundred yards, which is also the difference between the best teams and the worst teams in punt return yardage. Would we say punt returns don't really matter and even out over the course of the season? Certainly not.

But what's clear is that the teams penalized less often than their opponents were no better than the teams penalized more often than their opponents. Want proof?  Read the chart, or just consider this: The Arizona Cardinals were the best team in the league last year in terms of penalties.  If you need more proof of the mathematical type, there was a (very small) negative correlation coefficient between wins and net penalties (-.10) as well as wins and net penalty yards (-.08) in 2002.

And what is perhaps even more surprising is the discovery that the majority of Super Bowl champions have actually been more prone to penalties than their opponents in the regular season. What is going on here? I'm not sure, but I have a few theories:

  • Good teams have the lead late in the game, which means they're on defense against the pass more often. This makes them more likely to be called for defensive pass interference, which is the only penalty that can cost more than 15 yards.
  • Good teams are more likely to decline their opponents' penalties and have their own penalties accepted. All the NFL's statistics are for accepted penalties only; declined penalties are treated as if they never occurred. It would make sense that a good team is more likely to have a successful play and therefore decline an opponent's penalty, whereas a bad team is more likely to have an unsuccessful play and take the penalty yards.
  • Good teams are more aggressive, and while aggressiveness is usually a positive trait in football, it can lead players to be penalized.
  • Winning teams could be smarter about taking penalties at the right times. For instance, it's often advantageous to take a delay of game penalty rather than waste a timeout. (This only happens a few times a season and probably isn't statistically significant.)

When discussing penalties, it's important to keep in mind that, contrary to what coaches and commentators tend to say, penalties shouldn't really be called "mistakes." When an offensive lineman holds Michael Strahan, he didn't do it on accident. He did it on purpose because he knew Michael Strahan would beat him otherwise. He just hoped he wouldn't get caught. Ditto a defensive back interfering with Randy Moss. Yes, there are some penalties that are mistakes -- offsides, false starts, delays of game -- but even those would seem to happen more often against better opponents. I'd expect a tackle to be called for illegal procedure much more often against Jason Taylor than against some practice squad scrub. So when you see that the Giants' opponents were flagged for more penalties than any other team's opponents last year, don't assume the Giants just got lucky. The Giants certainly played a role in it. Also keep in mind that NFL officiating crews are not all created equal. Some crews call more penalties than others. But even if one team was stuck with a flag-happy crew more times than another team, it would make no difference in the net penalties shown here.

Here are the teams ranked from the 2002 regular season in order of their net penalty yards:


Team Penalties Penalty
Yards
Opponent
Penalties
Opp. Pen.
Yards
Net
Penalties
Net Pen.
Yards
W-L
ARI 76 617 111 969 +35 +352 5-11
PIT 90 712 106 927 +16 +215 10-5-1
KAN 75 700 100 827 +25 +127 8-8
NYJ 79 685 99 809 +20 +124 9-7
PHI 111 897 112 969 +1 +72 12-4
CHI 95 864 115 935 +10 +71 4-12
DET 104 916 114 981 +10 +65 3-13
SDG 100 805 103 854 +3 +49 8-8
NOR 119 911 110 953 -9 +42 9-7
NWE 108 895 99 928 -9 +33 9-7
JAC 89 685 96 717 +7 +32 10-6
GNB 108 913 98 945 -10 +32 12-4
BAL 101 846 104 874 +3 +28 7-9
SEA 100 792 99 816 -1 +24 7-9
BUF 112 1031 117 1053 +5 +22 8-8
IND 91 730 102 746 +11 +16 10-6
WAS 116 968 119 972 +3 +4 7-9
CAR 94 785 98 782 -4 +3 7-9
ATL 105 931 112 920 +8 -11 9-6-1
CIN 99 884 101 867 +2 -17 2-14
MIA 103 859 106 826 +3 -33 9-7
TEN 112 891 99 853 -13 -38 11-5
TAM 103 789 93 749 -10 -40 12-4
SFO 87 725 82 681 -5 -44 10-6
DEN 104 877 99 829 -5 -48 9-7
DAL 105 974 119 919 +14 -55 5-11
HOU 136 1011 102 955 -34 -56 4-12
NYG 113 955 120 897 +7 -58 10-6
CLE 107 845 91 726 -16 -119 9-7
STL 120 919 99 755 -21 -164 7-9
OAK 129 1094 103 787 -26 -307 11-5
MIN 137 1139 100 824 -37 -315 6-10
Correlation
Coefficient
with W-L
-.02 -.14 -.30 -.29 -.10 -.08  

Out of the 37 Super Bowl champions, 23 actually had more penalty yards than their opponents.  Here's a list of the past 20 Super Bowl champions with penalties listed for the teams and their opponents:


Team Penalties Penalty
Yards
Opponent
Penalties
Opp. Pen.
Yards
Net
Penalties
Net Pen.
Yards
02 TAM 103 789 93 749 -10 -40
01 NWE 92 802 93 839 +1 +37
00 BAL 95 730 84 535 -11 -195
99 STL 113 889 114 1007 +1 +118
98 DEN 115 1023 113 865 -2 -158
97 DEN 116 1006 130 1118 +14 +112
96 GNB 92 714 107 797 +15 +83
95 DAL 90 695 112 913 +22 +218
94 SFO 109 890 108 912 -1 +22
93 DAL 94 744 87 653 -7 -91
92 DAL 91 650 94 727 +3 +77
91 WAS 90 798 94 767 +4 -31
90 NYG 83 655 83 569 0 -86
89 SFO 109 922 75 581 -34 -341
88 SFO 115 986 76 603 -39 -383
87 WAS 82 691 98 801 +16 -110
86 NYG 96 738 119 988 +23 +250
85 CHI 104 912 118 944 +14 +32
84 SFO 100 884 91 723 -9 -161
83 LARAID 121 992 109 947 -12 -45

(Please note that the '87 Redskins' numbers include the three games with replacement players.)

So does this data say that penalties don't matter? It most certainly does not. We've all seen penalties that had game-altering implications. But penalties are probably less important than coaches and commentators would have us believe. And this probably deserves further study.

Posted by: Michael David Smith on 23 Dec 2003

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