Does 'Rubber Necking' happen after an accident? When two cars get into an accident the cars around them need to slow down to avoid hitting the cars involved in the collision. This causes a backup in traffic. People have often told me that traffic around an accident is caused by people 'rubber necking' or slowing down to see what is going on. In my experience most drivers will quickly speed up as soon as there is open road in front of them, regardless of if there is a car off the road nearby. Have there been any studies that prove that people slow down just because there is a car off the road? Or is the traffic just due to the initial slow down filtering itself out?

According to a page on rubbernecking from the UK's Highways Agency:

> Congestion caused by incidents is a significant cause of delay on the Strategic Road Network. In many cases, incidents can cause secondary congestion on the opposite carriageway due to road users slowing down to look at the incident scene (known as 'rubbernecking').

The Agency believes the problem to be so bad that it suggests putting up portable screens to block the accident scene from view:

> Blocking the passing drivers' view of the scene with an incident screen helps address this issue; work carried out by the TIM team has demonstrated the benefit of incident screens in reducing secondary congestion caused by 'rubbernecking'. Incident screens remain a key project within TIM and have been featured in the Bulletin on several occasions, the last article in June 2008 focused on a recent trial of a free-standing incident screening system in Area 5 .