October 24, 2011
The RAND Corporation today retracted the study "Regulating Medical Marijuana Dispensaries: An Overview with Preliminary Evidence of Their Impact on Crime" that was released in September.
Questions raised following publication prompted RAND to undertake an unusual post-publication internal review of the study. That review determined the crime data used in the analysis are insufficient to answer the questions targeted by the study.
The primary issue discovered during the internal review was that the data described as covering the city of Los Angeles and surrounding areas did not include crime data reported by the Los Angeles Police Department.
RAND researchers intend to conduct a new analysis once they have an adequate set of crime information and those results will be posted to www.rand.org. Because that work could take many weeks, RAND officials wanted to be clear that the study's findings cannot be validated at this time. [Update 12/2013: RAND no longer plans to publish a revised analysis.]
"This was a rare failure of our peer review system," said Debra Knopman, vice president of the RAND Infrastructure, Safety, and Environment division. "We take our commitment to quality and objectivity seriously so we have retracted the study in order to correct it."