A classic driving conundrum: When turning left off a street with a wide median, can you continue to drive after you've turned? If that question didn't make sense, take a look at the picture below. What do you do?

(image from google maps)

On Thursday's Brian Lehrer Show, former NYC Traffic Commissioner "Gridlock" Sam Schwartz took on the question he says he's "probably one of a handful of people in the city" qualified to answer. And that answer is... GO FOR IT!

According to Schwartz, the law states that as long as the median is less than 30ft wide, you can continue to drive once you've made the turn -- even if the light you're now facing is red. Many of NYC's medians are less than 30ft wide, and many NYC drivers mistakenly think they have to come to a full stop and wait for their new light to turn green.

Here's that intersection, again, annotated.

(thanks to Jessica Miller for annotating the picture)

Below, a simple step-by-step process for determining whether you can keep driving after you've turned left across a median:

• Make sure the light is green.
• If the light is green, put your car in park and put on the flashers.
• Get out of the car with a tape measure and measure the width of the median.
• Get back in the car, turn off your flashers and, if the light is still green, make the left turn.
• If the median is more than 30ft wide, stop.
• If the median is less than 30ft wide, you can proceed. It doesn't matter if the light is red or green.
• Check to see if there are other cars or pedestrians in the way. You still have to yield to them. This really matters.

Listen to Sam Schwartz explain the maneuver in the audio above. Hear his full segment on NYC's dangerous intersections on the Brian Lehrer Show here. You can also find another explanation in his book Gridlock Sam's Traffic Conundrums. Here's a PDF of that explanation.