Matthew W. Daus, who was nominated by Mayor Rudolph W. Giuliani in July to become the next commissioner of the taxi agency, said that his concern about the advertising signs was that streaming messages could distract drivers who try to read them and cause accidents. As the signs work now, they flash only nonscrolling ads, scores or stock market figures.
"We haven't really created a new forum for speech," said Daus, who added that other companies have expressed interest in trying to compete with Cohen. "We did that back when we authorized cab-top ads. This is just a new device for doing that."
He added, "I've seen them out there myself, and I think they're interesting."
The signs are powered by the cab's alternator. When the driver parks for a bathroom break or a meal, all the power and influence of the messages from multibillion corporations take a break with him.
"Oh, well, so he goes to lunch," Cohen said. "It goes off. No big deal. They don't all go to lunch at the same time, right?"



