PORTLAND -- A U.S. Department of Justice investigation concluded that the Portland Police Bureau engages in a pattern or practice of excessive use of force, specifically when dealing with the mentally ill, U.S. Attorney Amanda Marshall announced Thursday.

The investigation found such use of force violates the U.S. Constitution. Still, she said, the problems revealed in the probe are not unique to Portland and the vast majority of PPB's use of force falls within constitutional limits.

Portland Mayor Sam Adams said the report also found that law enforcement agencies are often the first responders in mental health crises, which points to a lack of options for adequate community-based mental health services.

The investigation was launched in June, 2011 to examine the use of deadly force against all citizens, with a specific look at the mentally ill.

Click to read the full DOJreport or the PPBresponse

The PPB had a high number of officer-involved shootings, especially those involving people with mental illness, Assistant Attorney General for the Civil Rights Division Thomas E. Perez explained at a press conference Thursday.

The findings concluded that too often Tasers and other uses of force were used when they were not necessary, Perez said.

He said training deficiencies within the department helped lead to the civil rights issues, and department has wasted no time in beginning the process of improving.

The biggest mental health facility now in the United States is jail, he added. That is wrong.

Adams pointed out that many of the deficiencies discussed in the findings originated before the current PPB administration--which he said has been aggressive in pursuing changes-- was in place.

Background: DOJ investigates Portland police use of force

The federal investigation followed several controversial police shootings, including the death of Aaron Campbell. The January 2010 incident sparked protests and one officer was fired for his use of deadly force.

Another high-profile case was the death of James Chasse, who died in PPB custody after an encounter with police in Old Town in September 2006. Officers said Chasse appeared to be urinating outdoors and when he tried to get away they tackled him. His autopsy revealed that Chasse suffered 26 rib fractures and a punctured lung.

Investigators said were looking for systemic problems within the PPB and also met with community leaders outside of the bureau.

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