In college football, staying disciplined isn’t just about the final score; it’s about who controls the game. You might zero in on talent or play-calling, but penalties tell you plenty about a team’s identity. To measure that, The Action Network built the Dirty Score, meaning a single number showing how undisciplined each team was from 2020 to 2024.
We tracked four stats per team:
- Penalty yards per game
- Penalties per game
- Penalty first downs per game
- Penalties per play
Each season, teams were ranked in those categories and given a Season Dirty Score: rack up more penalty yards or give up more first downs, and your grade slips. We then combined all five seasons into one overall Dirty Score, giving extra weight to teams that stayed dirty year after year. That way, one rough campaign won’t drag you down; this is about long-term habits.
Final scores run from 0 (cleanest) to 100 (dirtiest).
The Dirtiest College Football Teams Ranking (2020–2024)
Looking at the 2020-2024 stretch, New Mexico takes the crown for most undisciplined, posting a perfect Dirty Score of 100.00. The Lobos averaged 7.74 penalties per game, 68.30 penalty yards per game and 2.10 penalty first downs per game, while flags flew on 6 percent of their snaps, he highest rate in the nation.
Right behind them, UAB sits at 99.25, thanks to an NCAA-high 72.28 penalty yards per game and a constant stream of infractions. Toledo (98.51), Pittsburgh (97.76) and Miami (97.01) round out the top five. These are programs that didn’t just have one bad year, but racked up flags season after season.
Even big-name schools pop up here. Tennessee checks in at 94.78, Mississippi State at 94.03. For programs with that kind of history, seeing them regularly among the worst in penalty avoidance is pretty telling.
The Cleanest College Football Teams
At the other end of the spectrum, Air Force stands out with a Dirty Score of just 0.75. From 2020 to 2024, the Falcons averaged 3.76 penalties per game, 32.76 penalty yards per game and 1.26 penalty first downs per game, with flags on only 3% of their snaps. That kind of consistency set the bar for clean football these past five seasons.
Right behind Air Force:
- Iowa (1.49)
- Army (2.24)
- Michigan (2.99)
- Navy (3.73)
These squads kept costly penalties to a minimum year in and year out. Whether it’s coaching emphasis or just the way they play, they proved you don’t have to bend the rules to win. Fun fact: Michigan wasn’t just one of the cleanest teams — it was also one of the nation’s most successful over this span.
You can get into the full data and average scores for every team in the interactive tables below.
Methodology
Here's how we built the Dirty Score to rank every Division I FBS team’s discipline from 2020-2024:
- Goal: Capture on-field discipline with one number, the Dirty Score.
- Metrics (per team, per season):
- Penalties per Game
- Penalty Yards per Game
- Penalty First Downs per Game
- Penalties per Play
Normalization: We converted each metric into a z-score within its season, so 2020 numbers line up with 2024.
Season Dirty Score: Weighted average of the four metrics:
- Penalties per Game – 30%
- Penalty Yards per Game – 40%
- Penalty First Downs per Game – 20%
- Penalties per Play – 10%
Final Dirty Score: We averaged each team’s seasonal scores, giving extra weight to squads that competed in more seasons. Then we rescaled everything on a 0 (cleanest) to 100 (dirtiest) percentile scale.
Analysis Completed: August 2025
The raw data behind this project is available here. If you’re gearing up to watch college football and bet this season, get started by checking out our BetMGM Bonus Code or bet365 Bonus Code.
