A 1967 state law that requires drivers to keep at least one hand on the wheel effectively prohibits private companies from testing driverless car technology in New York, according to the Department of Transportation. And while the state Senate has passed legislation to allow testing of driverless cars, the DOT urged the City Council on Friday not to support that legislation until New York City has had a chance to present safety concerns specific to driverless cars on congested, narrow city streets.