NEW YORK (WABC) -- Manhattan is set to begin its new marijuana policy Wednesday.This means the Manhattan District Attorney's Office will no longer prosecute marijuana possession and smoking cases.The new policy was designed to reduce the number of marijuana prosecution cases from 5,000 a year to fewer than 200."Our research has found virtually no public safety rationale for the ongoing arrest and prosecution of marijuana smoking, and no moral justification for the intolerable racial disparities that underlie enforcement," Manhattan District Attorney Cyrus Vance said in a statement.Vance also encouraged lawmakers to legalize marijuana.This follows the NYPD's new plan to issue summonses instead of arresting offenders for most public marijuana offenses . This policy is set to start next month.Mayor Bill de Blasio also asked for a change in marijuana enforcement laws.There has already been a similar move in Brooklyn, where the DA also stopped prosecuting low-level marijuana cases.Manhattan's DA said there will be some exceptions, and some marijuana cases will still be prosecuted.Those exceptions include cases against sellers and those who have demonstrated a public safety threat, such as people under investigation for violent and serious crimes.----------