NEW YORK (CBSNewYork/AP) — Mayor Michael Bloomberg says the fact that officers are recovering fewer guns through stop-and-frisks is an indication the program is working.

WCBS 880’s Marla Diamond reports

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On his weekly radio show, Bloomberg said he believes the stop-and-frisk program is lowering the city’s crime rate, but conceded it could be applied more effectively.

Police Commissioner Ray Kelly says every situation is different.

“This is situation driven. It depends on what conditions officers encounter on the street,” he told WCBS 880’s Marla Diamond.

Kelly says he’s not considering changes to the program.

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“I think the effectiveness of the program is shown in the fact that under the Bloomberg decade, we’ve had a 51 percent decrease in murders in the city,” he said.

Civil liberties advocates have denounced the program as racist and often unnecessary.

Earlier this week, civil rights groups announced a lawsuit against a program allowing officers to patrol private apartment buildings and perform stop-and-frisks there.

Last year, officers stopped and questioned 684,330 people on the streets under the stop-and-frisk program, a record since the NYPD began tallies in 2002.

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(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)