Zero tolerance means precisely that: zero tolerance—even for a student who had a very good reason to pick a fight with the school bully.
A student at Huntington Beach High School in California has been widely celebrated all over the internet for protecting a fellow student—a blind teenager—from a bully's violent assault. Video footage of the incident—courtesy of The Daily Mail—clearly shows the bully repeatedly punching the defenseless blind teen in the face until the third student walks up and knocks out the bully with a single punch. The intervener then assists the blind teen in escaping to safety.
Police later arrested the bully (he is unnamed in news reports, as is his victim, and the hero). I've argued that schools should not involve the cops in minor disciplinary issues, but the bully's actions look to me like they crossed a line. This was not a trivial scrap, and it wasn't a fair fight. The bully aimed for his defenseless opponent's face. The cops want to charge him with misdemeanor battery, and it's hard to disagree with that decision.
The other student—the rescuer—will also be punished, since violent behavior is prohibited in all circumstances, even when it is necessary to protect the well-being of another student.
The school suspended the student from the football team, and are investigating the incident to determine whether harsher measures are warranted. Meanwhile, the kid's supporters have started a petition to convince the district to reconsider. According to Hot Air:
The online petition to reinstate him is already north of 25,000 signatures as I write this. I assume the school will eventually cave and vacate the suspension at least, partly because even the criminal code in a state as blue as California permits violence in defense of another(provided you use no more than is reasonably necessary to end the threat) and partly because America looooves rough justice and is going to hound school administrators until they do the right thing here.
This is what zero tolerance looks like: harsh, automatic punishments for teens who broke stupid rules, or had good reasons to break sensible, inflexible rules. This is why a school called the cops on a 13-year-old who kissed a girl. It's why administrators routinely suspend students who play with toy guns, or make shooting gestures with her hands, or make up stories about guns. It's why a student who didn't bring drugs to school was disciplined for bringing drugs to school. And it's why the temporary arrest of Ahmed Muhamed is part of an outrageous pattern of paranoid school policing, regardless of whether he built his clock himself.
[Updated at 10:00 a.m.] On Twitter, the teen clarified that he was never kicked off the football team—that story was "made up" by the media, he said. The school district also denied that he would be suspended; whether the petition influenced that decision is unclear. For me, the fact that 20,000 people expected the hero to get unfairly railroaded by the system is still quite a testament to the ubiquity of zero tolerance.