The most divisive issue facing New Yorkers in 2013 is "stop-and-frisk", a tactic used by law enforcement to stop, question, and frisk people suspected of a crime. From Bed-Stuy to the Upper West Side, the single most commonly-asked question as I campaign for mayor is: "How do you feel about stop and frisk?"

"Abolish it!" some say. "Keep it. It works!" others say. Unfortunately, this complex issue is being reduced by some to a mere litmus test in which you are either "for" or "against". Fortunately, New Yorkers care too much about their neighborhoods, their families, and their city to buy those arguments. They want a strong police department to keep guns off of the street, and they want to be able to walk around without fearing an unnecessary police encounter.

So what can we do? First, we have to recognize that the fourth amendment protects all Americans, regardless of race, from unreasonable search. Second, we have to recognize the difference between stop-and-frisk, a legal police tactic upheld by the Terry v Ohio case, and its application in New York City, where an especially wide net has been cast. Stop-and-frisk is a valuable police tool, but its application should be amended to ensure that no one is stopped in violation of the constitution.

So how do we do that?

We need to go straight to the root of why so many young people are being arrested: marijuana.

Overwhelmingly, New Yorkers arrested during stop and frisk encounters are charged with marijuana possession. In the past decade, New York City spent $1bn and 1m police hours prosecuting 440,000 marijuana arrests. Fifty percent of those arrested were under the age of 21; 85% of them were black or Latino.

What have we accomplished with these arrests?

Not very much. Marijuana is more prevalent than ever, with 1.8 million New York State residents using it. More than a third of New York City youth use it, just slightly less than those who smoke cigarettes or drink alcohol. We are spending precious taxpayer money and police time, giving thousands of otherwise law-abiding young New Yorkers a permanent criminal record, and accomplishing little. No matter how you crunch the numbers, the conclusion is the same: current marijuana laws are creating more problems than they are solving.

History offers a clear path forward: taxing, regulating, and ending the prohibition of marijuana.

By legalizing marijuana, we can allow officers to focus on patrol and build a rapport with communities. This will improve trust and the flow of information, enabling cops to more easily identify real troublemakers and drastically cut down on stops of law-abiding citizens. We can devote those 1m police hours and $1bn law enforcement expenditure to hire and train more police officers, address local quality-of-life crimes, and improve clearance rates for homicide, rape, and robbery.

By regulating marijuana, we can put black-market drug dealers out of business and eliminate the rebellious allure that attracts young people. By taxing marijuana, we can raise billions of dollars in new revenue to pay teachers better, create pediatric wellness centers, invest in schools, and expand health services to prevent and treat drug addiction.

I spent 11 years as a New York City public school teacher and worked as a drug prevention coordinator. I spent 15 years on the City Council public safety committee, hiring more police and equipping them with tools to protect our city. I don't like marijuana, and I don't think people should smoke it. I have never even tried it myself. But I do believe that the time has come to act.

New York City cannot afford to be divided or to throw away money on policies that don't work. If we take this politically courageous step, we can reduce stop-and-frisk encounters, reduce drug availability, and raise significant revenue to help our cops and our kids for years to come.