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Overbooking a flight is perfectly legal according to federal law.

But should it be?

When the United Airlines incident involving violently removing a doctor who refused to volunteer to leave the flight occurred, millions of people were asking why. Why was he removed. Why did he have to give up his seat. Why was the flight overbooked in the first place. Well, we know the answer to the last question.

Know that the doctor in question isn't the only person to be rescheduled for another flight. This happens annually to 40,000 people. It's that common. Why is that allowed, and why is it legal?

Airlines know that on average, a percentage of passengers will not show up for their flight, leaving them with empty seats. Obviously, the airline will lose revenue from not having bodies in seats. Federal law allows this practice, and also doesn't limit how much an airline can overbook a flight.

Even more surprising is federal law says the airline doesn't have to provide any additional compensation to a passenger who is booted from a flight. They simply have to get said passenger to their destination within a certain time frame.

Could the United incident be prevented if the flight wasn't overbooked in the first place? We can't answer that, but we do know that flights out of Boise have no record of forcibly removing passengers.