The ATA is warning against the illegal practice. ATA Chair Mark Parry has spoken about the dangers in a series of radio interviews this week. “In addition to being dangerously ambiguous, using your turn lights to show that it’s safe to overtake is illegal. “Under the road rules, you should only use your direction indicators when you’re required or as part of the vehicle’s hazard warning lights,” he said. Parry added that motorists should only overtake trucks if they had a clear view of any approaching traffic and could see it was safe.