At a news conference, Stamper said he hoped his announcement would remove politics from the examination of what went wrong in handling the world conference.
The scenes of what appeared to be police excess in Seattle have now become familiar, reports CBS News Correspondent John Blackstone. But when the city's police chief announced his resignation Tuesday he apologized, not to demonstrators, but to his officers.
"Clearly our officers faced overwhelming odds," Stamper said. "They were on the lines for long periods of time and they deserve every form of tangible as well as emotional support that we can give them."
There was criticism of Stamper's handling of the protests from the very beginning. At first police did little to contain demonstrators. Officers were nowhere near when masked protesters began smashing windows and looting.
Then police adopted tough new tactics -- moving aggressively against any suggestion of trouble. Demonstrators and Seattle residents complained the police were going overboard
"I saw people who'd just been pepper-sprayed in the face sitting down on the ground in pain, with a police officer standing directly above them pop-popping shots down into them from inches away," said Seattle resident David McGraw.
But the police grumbled they were dangerously outnumbered and overworked, not given the support they needed to keep the peace.
"To the extent they feel that they didn't get that, I personally apologize to them," Stamper said.
Stamper says he planned to resign early next year anyway. He'll stay in the job until the end of March while the city investigates the events last week.
In spite of criticism from both sides, Stamper defended police actions last week. In a volatile situation he said no one was killed or even seriously injured.
Mayor Paul Schell praised Stamper for his "sense of duty and sense of responsibility." Schell said he had tried to dissuade Stamper from leaving when he was told of the chief's decision Sunday.
Schell, who also has come under intense criticism for his handling of the conference and police response, told the news conference that he does not intend to resign. "I'm going to see this through," he said.
In a letter to Schell and an interview with the Seattle Post-Intelligencer Monday, Stamper said he decided last month to retire in January for other reasons but moved up the announcement because of the WTO disorders, which have been blamed for damage and business losses approaching $20 million.
Schell told the paper he would accept the resignation, which takes effect in March.
President Clinton nearly canceled his WTO visit after months of hailng the sessions as vital to U.S. free-trade interests because of the disorders, Stamper revealed.
"We all had a very serious conversation about whether all the venues the president would visit were secure," he said.
King County Sheriff David Reichert and some of Stamper's own officers openly blamed him and Schell for the vandalism and scattered violence Nov. 30. Police critics said tear gas and rubber bullets were fired indiscriminately and innocent workers, shoppers and residents were swept up in the arrest of more than 500 people Nov. 30 and Dec. 1.
No serious injuries or deaths resulted, but downtown merchants have reported more than $2 million in property damage and $17 million in lost retail sales.
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