If you hesitated, you're not alone.

A Muni rider recently got into a shouting match with a driver after stepping off a train, only to have the motorist barrel forward and argue that a concrete median meant she didn't have to yield. The rider pointed to the stickers plastered on the train itself — "Do Not Pass" — and got an earful in return.

So who's right? The law is unambiguous. California Vehicle Code and SFMTA's own rules require cars to always stop behind trains where passengers board or exit in the street — including at so-called "clear zone" locations with medians. As one SF resident put it plainly: "The law requires cars to always stop behind trains where passengers get on and off Muni in the street. Do not pass until the doors are closed."

That's not a suggestion. It's the law.

Another local pointed to a particularly notorious stretch: "Ocean and Miramar. Cars are supposed to stop for people to get out of the train and only go 10 mph when the doors are closed. Most don't follow the rules."

And that's the real story here. The rules exist on paper. They exist on stickers. They exist on the SFMTA website. What they don't exist as is an enforced reality on San Francisco streets.

This city spends enormous sums on Vision Zero campaigns, bike lane bollards, and pedestrian safety studies. We have an entire bureaucratic apparatus dedicated to the idea that no one should die on our streets. And yet a person stepping off public transit — doing exactly what the city tells them to do, riding Muni — can't count on a basic traffic law being followed or enforced.

The median doesn't absolve drivers. The concrete island is there to provide an extra buffer, not to replace the legal obligation to stop. Treating it as a loophole is how someone gets killed.

SFPD and SFMTA could solve this tomorrow with a couple of targeted enforcement stings at high-violation stops. It wouldn't cost much. It would save lives. But that would require the kind of straightforward, results-oriented governance that this city perpetually struggles to deliver.

In the meantime, keep your head on a swivel when you step off that train. The sticker says "Do Not Pass." The driver behind you might not have read it.