The longest three seconds in basketball

How to fix the NBA's defensive three seconds problem

If I only had a few seconds left to live, I’d choose to spend it in the paint on an NBA court. Because in there, three seconds can last forever.

This season, teams have been called for Defensive Three Seconds 285 times, which averages out to about once every three games. If the season ended today, that would be the lowest rate at which it’s been called in the last twenty years, according to pbpstats.com.

Part of the decline can be explained by the fact that offenses are more spread out so defenders are spending less time lingering in the paint and guarding their man. But the rate is also declining simply because referees aren’t enforcing the rule.

Because Defensive Three Seconds is called so infrequently, not everyone reading this will be familiar with it. So let’s quickly refresh our memories on what a Defensive Three Seconds call is and why its lack of enforcement matters.

In the NBA, a defensive player is only allowed to stay in the paint for a total of three continuous seconds unless they’re actively guarding someone. A defender can restart the three second counter by completely exiting the paint or by showing that they’re guarding someone — this can be achieved by doing something as simple as tagging an offensive cutter running through the lane. The best defenders have an internal timer that tells them when they need to refresh the three second counter, a practice known as “2.9-ing.” Brook Lopez is a master at this.

Defenses prioritize taking away shots at the rim, which are still the most efficient shots in basketball. Parking a big man in the paint for longer than allowed is a simple and effective way to deter opponents from getting easy looks at the basket. Last year, Tom Haberstroh published an article for NBC Sports detailing how the Raptors were finding success late in games by having a defender camp out in the paint and blatantly disregard Defensive Three Seconds. Surely, other teams are aware this rule exists in name only and it’s likely that some are using it to their advantage. And if they aren’t, they sure as shit should be.

Check out the chart below, which shows the distribution of when common fouls and violations are called throughout an NBA game.

Personal Take Fouls (the NBA’s play-by-play tag for Intentional Foul) are excluded from this chart since those spike at the very end of the games.

Notice how unusual the shape of the distribution is for Defensive Three Seconds relative to every other kind of foul and violation. In all other cases, referees tend to blow their whistles at approximately equal rates in the first and second half. That’s what we should expect to happen.

But Defensive Three Seconds spikes early in the first half and gradually declines throughout the game. It doesn’t make sense. There’s nothing inherently different about the second half of NBA games that would make teams less likely to commit Defensive Three Seconds. And this isn’t an anomaly that’s limited to this weird season either. Russell Goldenberg and I published a short video about this quirk for The Pudding back in 2019.

You might think that as the game goes on, defenses become more alert and are less likely to commit unforced errors. But that theory doesn’t hold up when we examine the data - which calls are made and which ones aren’t - when the game is on the line.

Any game where the score is within three points in the last two minutes triggers the publication of a Last Two Minute Report. In these reports, NBA officials review every play from the last two minutes of the game and assess whether the referees made the right call. What’s interesting about these reports is that the assessment isn’t limited to the calls the referees made, but also the ones they didn’t.

From these reports, we see how often referees made a:

• Correct Call (CC)

• Incorrect Call (IC)

• Incorrect No Call (INC)

Thanks to @atlhawksfanatic on Twitter, who has cleaned and categorized every Last Two Minute Report since 2015 on GitHub, we can look back at the last six years to see how often each foul call was correctly made in high pressure moments. In other words, we can see how often referees got the call right when the game mattered most.

Since 2015, there have been 196 confirmed instances of Defensive Three Seconds in the last two minutes of close games. It was only called twice. The defense got away scot-free the other 194 times. If I were Markoff Morris or JaVale McGee, the two players that were nabbed for committing Defensive Three Seconds, I’d have a bone to pick with the NBA.

A one-percent enforcement rate means committing Defensive Three Seconds in the NBA is the equivalent of jaywalking in New York City. It’s against the rules, but no one really cares.

So to summarize what we know: referees call Defensive Three Seconds less often as the game goes on. But by the NBA’s own admission, teams continue to commit the violation late in games. In short, all evidence suggests that referees aren’t as strict about enforcing this particular rule throughout the game.

It’s probably not fair to paint all referees with the same brush. Some appear to be more vigilant about calling Defensive Three Seconds than others. Based on my own unofficial referee database, which includes every foul and violation called by every referee since 2016, referees like Mark Lindsay stand out for their willingness to enforce the rule.

It’s worth emphasizing that the sample sizes here are fairly small so an updated version of this chart in five years could paint a different picture. Still, I think the takeaway is pretty clear: teams are committing Defensive Three Seconds at a much higher rate than it’s actually being enforced.

This presents a good opportunity to discuss one or two possible rule changes to fix this problem.

The first, is to just get rid of the Defensive Three Seconds rule entirely. The college game doesn’t use it. Nor does FIBA. Teams hate it. Referees ignore it. We’d probably be better off without it.

Furthermore, the NBA has made plenty of rule changes in recent years to benefit the offense at the expense of the defense. Giving something back to the defense could re-level the playing field somewhat by changing the math on which shots are actually most efficient. Suddenly, that 15-foot jump shot looks a lot more appealing when Joel Embiid is camping out in the paint.

Since removing Defensive Three Seconds would probably result in fewer drives and dunks, I doubt the NBA would ever go for it. That leads me to my other and more prefered rule change.

If referees are unintentionally¹ letting Defensive Three Seconds slide, then the best idea is to add a fourth official to every game. The NBA has been using three referees since the late 1980s, back when the game looked a lot different than it does now. Players are so much more spaced out and the area that referees have to monitor has never been larger. With so much action occurring out on the perimeter, it’s harder for referees to keep an eye out for Defensive Three Seconds violations.

Just look at the difference in the number of players crowded in the paint in the two photos below. The first comes from the 1991 NBA Finals while the second comes from last night’s Bucks and Net games.

A screengrab from the 1991 NBA Finals. Notice the density of players in the paint.

A screengrab from last night’s Bucks x Nets game. Notice the lack of players in the paint.

It’s unreasonable to expect referees to be able to catch every infraction given the dramatic increase in spacing. Bringing on a fourth referee whose main job it is to watch out for Defensive Three Seconds (and Offensive Three Seconds) would solve this problem. Also, adding a fourth referee whose responsibilities are limited at first could create a simple pathway for onboarding less experienced officials into the NBA before they’re thrown into the fire, like they are currently.

Ultimately, this only matters if the NBA thinks it’s a problem. I’m sure someone at the league office has crunched the same numbers and arrived at the same conclusions. I doubt they’d ever admit it, but I’m guessing the NBA has decided to let this rule quietly fade into obscurity because enforcing it might ruin the overinflated offensive bonanza going on right now.

1. Here’s one tin-foiled hat reason to think the lack of enforcement might be intentional: A few years ago, an anonymous source told ESPN that one of the ways that Tim Donaghy, the former referee that went to jail for betting on NBA games that he was officiating, would tip the scales in his favor was by calling illegal defense early in the game.

"He said he liked to call an illegal defense call, right away, in the first minute." That way, the gambler said, Donaghy could force the side he'd picked against to play a little less aggressively on defense. "He said he'd pick on the big center, or the most valuable player of each team, and he'd try to get them in foul trouble."

That could at least partially explain why referees are more likely to call Defensive Three Seconds early on in games.