Just because someone tells you in San Francisco that San Francisco is not going to prosecute you for doing something, that does not make it legal. It remains illegal after federal law.

September 4, 2018

U.S. Deputy Attorney General Rod Rosenstein, on cities' pursuit of supervised injection sites where people can safely use drugs and avoid overdosing. It marks the first time a high-ranking federal justice official has commented on the issue.

Source: NPR