Its advice is clear: never exceed the speed limit, regardless of perceived leeway or officer discretion. Common speed camera mythsHere are some other common speed camera myths :Is it true that speed vans have to be visible at all times? Is it illegal to flash your headlights to alert motorists of a GoSafe speed van? If drivers choose to flash to warn others about a speed van, they could be in breach of the law. He said: "It doesn't bother me that people flash to warn them of the speed van - I just want to educate people and the van to act as a speed deterrent."