The ACLU report released Tuesday found that black people in San Francisco were 4.3 times more likely than white people to be arrested for pot possession in 2010, the year the civil rights organization looked at statewide crime and census data.
There were 192 arrests of black people for marijuana offenses versus 44 for whites that year, according to the ACLU report, among the highest in California and nearly twice the state average.
The city's Police Department issued a statement Wednesday saying the department "does not racially profile," adding that "no one is arrested in sufficient numbers for marijuana possession here in San Francisco to substantiate such a claim."
The department's statement cited arrest numbers for 2011, when only 11 people were arrested for misdemeanor marijuana possession in San Francisco. That year was also police Chief Greg Suhr's first as the city's top cop.
The statement said Suhr on Wednesday reviewed all 11 cases and found that in all of them, the marijuana charges were secondary to other charges such as outstanding warrants, possession of illegal weapons or being drunk in public.
Of the arrestees, five were black, five were white and one was Hispanic, according to police.
"It is evident that the misdemeanor marijuana arrests ... were made using sound police procedure pertaining to criminal activity and not by racial profiling," the statement said.
The ACLU report looked at arrest rates county-by-county across all 50 U.S. states and criticized law enforcement for wasting too many resources on marijuana while failing to diminish its use or availability.
The report said a focus on marijuana, now legal in multiple states but still illegal under federal law, "has needlessly ensnared hundreds of thousands of people in the criminal justice system, had a staggeringly disproportionate impact on African-Americans, and comes at a tremendous human and financial cost."
The ACLU report recommended law enforcement agencies deprioritize enforcement of marijuana possession and that the drug be legalized throughout the country.