As Americans increasingly espouse support for medical marijuana, Los Angles voters this year opted to cleanse the city of angels of some of the industry’s seedier elements.

Scores of medical marijuana dispensaries either closed or would soon close operations in the city following the implementation of a new referendum law, which restricted licenses to only shops which operated prior to an attempted 2007 moratorium. Approved by voters in April, Measure D authorizes the 134 pre-existing dispensaries to continue operating within the city, while sharply increasing taxes.

Already, the shuttering of marijuana businesses in the city has garnered at least one documentary series: Weed Wars, produced by the Discovery Channel. Thirty-eight dispensaries have already closed, with another 42 planning to shut down soon, City Attorney Mike Feuer told The Los Angeles Times Saturday. "We're going to see a major difference in the way that operators and property owners perceive the city.”

The new law also requires marijuana dispensaries located within 600 feet of a park, school, or child-care facility to move to another location. The harsher new regulations follow legal maneuverings by the city during the past few years that reduced the total number of dispensaries from 1,000 at its highest point. The city council in 2010 passed an ordinance attempting to reduce the number of marijuana shops to 70, although the regulation expired in 2012 following lawsuits by dispensaries. After again approving the ban, the city opted to try another tack, rescinding the ban once marijuana opponents had collected enough signatures for a referendum.

Interestingly, some dispensaries have filed suit in federal court challenging aspects of the referendum law, even though medical marijuana remains illegal under federal law. “We want those dispensaries to be recognized as meeting the requirements of Measure D, dispensary attorney David Welch told The Los Angeles Times.

Prior to this year’s White House decision to respect state and local marijuana laws, U.S. attorneys had raided clinics in Los Angles and elsewhere, following California’s allowance of medical marijuana in 1996. The issue remains one of the most hotly contested areas of U.S. jurisprudence, with implications for both substance abuse and the treatment of chronic diseases and conditions.

Below is an interview of the stars of Discoery Channel's Weed Wars on Fox New's Bill O'Reilly.