Tailgating, no matter how it happens, is dangerous. Take one drive across town and you'll see that people do it constantly, but the risks are enormous.
It massively increases the odds of a chain-reaction accident. It also increases the odds of an easily avoidable accident when something unexpected happens. A dog runs into the road, for instance, and you slam on the brakes. You safely miss the dog and then the driver behind you slams in your car.
It's that driver's fault. But that doesn't make this any less dangerous.
Typically, tailgaters fall into two categories: passive and aggressive. Both are dangerous, but in different ways.
An aggressive tailgater is likely someone who wants you to move so he or she can pass. This is more dangerous because it can lead to road rage and it's a pointless risk, but it's less dangerous because you can usually allow him or her to pass and the danger -- to you, at least -- is gone.
A passive tailgater probably doesn't even know he or she is driving so dangerously. That driver doesn't want to pass. There's no anger involved. Instead, the driver just thinks that being a half a second behind your rear bumper is safe.
To be clear, it's not. Not at all. But the road is full of unsafe drivers who are honestly ignorant of the way they put others in danger. This can actually be more dangerous because it may last longer and because it could indicate that the driver is either not very experienced or not aware of basic road safety practices.
Either type of tailgater can cause an accident and injure you in a split second. When this happens, make sure you know all about your legal rights.
Source: Confused, "How to deal with tailgaters without losing your rag," Owe Carter, accessed Aug. 24, 2017