In the 1970's all of the states that previously has not permitted right turns on red at traffic signals (RTOR) adopted the so-called western law permitting RTOR after stopping unless specifically prohibited by a sign. Such turns are now allowed nationwide except in New York City.
Washington, D.C., Insurance Institute for Highway Safety IIHS, 1982, 3 p., ref.; Research Note No. 104 [published in: Accident Analysis & Prevention, 16(4), pp. 241-245, 1984]
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