Marijuana had been used along the Mexican border for many decades without much concern. However, there was a significant upsurge in migration following the Mexican Revolution of the early twentieth century. States passed antimarijuana laws, giving police a legal pretext to search and question migrants and create a climate of fear. In the North, marijuana was criminalized after becoming more popular among African Americans in the big cities. Its close association with jazz and black culture led to a moral panic. These twin forces came together nationally with federal prohibition in 1937.
