The UK's Crown Prosecution Service is appealing its case against Charles Glendinning, 56, to the House of Lords. In October, the High Court found Glendinning not guilty of obstructing justice when he waved at motorists to warn them of an upcoming speed trap. The judges determined that there was no evidence that his actions actually slowed anyone down. If successful, the Crown's appeal would set a precedent outlawing the custom of flashing headlights or waving to let passing drivers know about nearby speed cameras.

Some safety activists are saying this case is proof that speed cameras are more about making money than reducing speeds.

"The camera partnerships tell us continually that: 'they don't want our money, they just want us to slow down,'" Paul Smith, founder of the Safe Speed road safety campaign said. "They can't have it both ways. Motorists warning others of speed traps is extremely effective in slowing traffic. If they don't want our money, then why appeal this case?"

In 2004, Stuart Harding, 71, was fined £364 (US $626) for displaying a sign, "Speed Trap -- 300 yards ahead."