"I couldn't have done better if I rented an airplane with a banner and put billboards up all over town," he said.
Still, he isn't planning on more sidewalk scrawls.
"I'm going to think of a more creative way to get my message across," he said.
The judge, who imposed a gag order on participants during the trial, refused to allow Olson's attorney to argue that the messages were constitutionally protected free speech. Instead, the attorney argued the messages caused no damage and were not malicious.
The prosecution was the latest tiff between San Diego's mayor and elected city attorney. Earlier this year, the mayor was a witness at a trial on behalf of an animal-rights activist for seals who was prosecuted for removing a flag at a beach that was declared open to the public. After the testimony, activist Bryan Pease pleaded guilty to misdemeanor trespassing.
Filner, who last month used his veto power to cut $500,000 from the city attorney's budget, crashed a Goldsmith news conference in February amid a dispute over how to spend money to promote tourism. Filner accused the city attorney of "unethical and unprofessional conduct," saying he was giving legal advice through news media.