Twitter user @RyanGHaughton posted the photo of Ford holding some papers in his right hand while behind the wheel of his black Cadillac Escalade on the Gardiner Expressway, and tweeted later traffic was moving about 70 kph (43.5 mph) at the time.
Asked about the photo by a reporter at a news conference Ford held to promote an upcoming trade mission to Chicago, the mayor said he "probably" was reading while driving.
"I'm busy," Ford said. "I'm try[ing] to catch up on my work and you know I keep my eyes on the road, but I'm a busy man."
Asked if he saw a problem with reading while driving, Ford repeated that he is a busy person.
"... I don't know what that has to do with a trade mission, but anyways. Ridiculous questions sometimes, seriously," the mayor said.
Toronto police Sgt. Tim Burrows posted on the department's official Facebook page Tuesday afternoon that reading a piece of paper while driving is not a violation of the distracted driving law, but a driver could be charged if "the driving behavior constituted a specific offense."
The officer urged Ford to "please get a driver."
"It is obvious that you are busy enough to require one and no amount of money you are saving by not having one is worth the life of one of your citizens," Burrows wrote.
The CBC said Ford has resolutely refused to get a chauffeur, despite others, including his brother, urging him to do so.
The mayor has been accused of other driving miscues, including illegally dialing and talking on his cellphone, the CBC said.