Harris was joined at a South of Market district gas station by state and local air quality officials to address what Harris called "environmental crime."
Such crimes include so-called "clean piping," when smog check station workers use one vehicle's clean emissions test to fraudulently hand out smog certificates for other cars that have not been tested.
"Our state has long been a leader on the issue of environmental protection," said Harris.
"We cannot afford any breakdown in the systems that keep high-polluting vehicles off our roadways and their dirty emissions from tainting the air we breathe," she said.
Harris highlighted the recently resolved case of one San Francisco smog check station operator accused in 2008 of six clean-piping incidents.
Ivan Arturo Mendoza, 26, pleaded guilty in March to two felony counts of knowingly accessing a computer system with intent to defraud, according to prosecutors.
"Anyone caught issuing fraudulent smog certificates should know that they will be held to answer for these crimes that endanger our environment," said Harris.
Mendoza was sentenced Monday to five years of probation, according to the District Attorney's Office.
As part of the sentence, he was required to surrender his smog check licenses and will be banned for five years from re-applying for them. He also had to surrender two smog-testing machines -- worth between $8,000 and $12,000 -- to be donated to local schools for vocational training.