SAN FRANCISCO (Reuters) - San Francisco prides itself on helping the homeless, and it even created a special committee for grievances from those kicked out of shelters.

But this month, it began a new experiment that treats the homeless more harshly than the city's other policies. After lengthy training, police began enforcing an ordinance that bans sitting or lying on sidewalks during daytime hours.

The measure, which was approved by 54 percent of city voters in November, has drawn criticism from homeless groups and the down-and-out themselves.

The new approach comes at a time when the city is working to bolster tourism and local businesses in a tough economy.

Many residents have welcomed the ordinance, which was spearheaded by a neighborhood group from 1960s counterculture haven Haight-Ashbury.

And police say enforcement is still driven by compassion.

"When you see people down on their luck, you're not trying to put them in jail -- you're trying to get them what they need," said San Francisco Police spokesman Troy Dangerfield.

But while Dangerfield said the goal is not to issue citations, police say they have given more than 45 warnings to homeless people since they began enforcement on March 11.

There is some bite to the so-called Sit-Lie ordinance, which applies from 7 a.m. to 11 p.m. First-time offenders receive a verbal warning, while second-time violators can be cited and fined $50 to $100.

Further offenders are subject to fines up to $500, and community service or jail time could also be required.

Kieran, a 23-year-old homeless man from Canada who declined to give his last name, received a warning slip from police.

"You're not allowed to sleep anywhere, to sit anywhere, to lie anywhere," he said. "So where are you supposed to go?"

A 2009 study by the National Coalition for the Homeless found that 30 percent of U.S. cities it surveyed prohibited sitting or lying in certain public places.

In San Francisco, with a population of at least 6,000 homeless people, the impetus came from Haight-Ashbury, where Ted Loewenberg, president of the neighborhood's Improvement Association, rallied enough support to get then-Mayor Gavin Newsom interested in the issue.

That paved the way for the ordinance being approved by voters.

"San Francisco has had a history of being a compassionate city in many ways, but simply giving away the store was not part of the equation," he said.

Loewenberg said Haight-Ashbury had a significant problem with sometimes thuggish homeless people filling streets.

The city has an extensive program called Project Homeless Connect which links homeless people to city services, welfare programs and job search resources, said Phil Arnold, finance director at the city's Human Services Agency.

A Shelter Grievance Advisory Committee oversees the grievance process for homeless people ejected from shelters.

But homeless advocates say city residents, who overwhelmingly elect liberals to office, remain skewed against the poor and the Sit-Lie ordinance demonstrates that.

"San Francisco has traditionally been conservative when it comes to its own poor people," said Jennifer Friedenbach, executive director of the Coalition on Homelessness.

(Editing by Alex Dobuzinskis and Ellen Wulfhorst)

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