The body of a mentally ill black woman who was shot and killed by police was brought to Phoenix City Hall today by community activists and the slain woman's family, who demanded an external investigation into her death.

Michelle Cusseaux, 50, was fatally shot by Phoenix Police Officer Percy Dupra on August 14, after police say she threatened officers with a hammer when they went to serve a court order to deliver Cusseaux to a mental-health facility.

Community members have joined Cusseaux's mother in calling for an independent agency to investigate the killing, in addition to the Phoenix Police Department's own investigation, although Phoenix police haven't agreed to seeking an external investigation.

"We've had to take drastic measures," Cusseaux's mother Frances Garrett said, standing beside her daughter's casket outside City Hall.

See also: -Phoenix Protesters Decry Shooting of Michael Brown; More Rallies This Weekend

Earlier this week, Phoenix Police Chief Daniel Garcia announced that his department's officers will have to undergo more training on how to deal with citizens with mental-health issues, and that he's ordering more body-mounted cameras for officers.

Garcia released a statement promising a full investigation:

"My responsibility is to ensure that the investigation into this case is thorough, prompt and fair, and I know that doing so is critical for the residents we serve to trust and have full confidence in the department's ability to conduct its day-to-day operations. Answering the questions of Ms. Cusseaux's family is a priority of mine. "The Phoenix Police Department is currently conducting two investigations into this incident, including a criminal investigation. In addition, I have asked Maricopa County Attorney Bill Montgomery to conduct a second - and independent - review of the criminal investigation. Further, the County Attorney's Office, which had staff on-scene during the investigation, will make the final case decisions and disposition."

Sabinus Megwa, an attorney for the family, said that's not good enough. He said he's let Garcia and Mayor Greg Stanton know they want an outside agency to investigate the shooting, and said he feared the Maricopa County Attorney's Office will "basically rubber-stamp what [Phoenix PD's investigation has] found."

If Phoenix police don't seek an investigation from another agency by next week, these activists plan on turning their detention to the Justice Department, and seeking a federal investigation.

"There are a lot of mentally ill people in this city, and we don't want this to happen to anyone else," Megwa said.

Before Cusseaux's body was brought to City Hall today, Mayor Stanton and Chief Garcia agreed to participate in a community forum this weekend that's advertised as "an open and respectful discussion on what Ferguson [Missouri] could mean right here in Phoenix."

In Ferguson, an 18-year-old unarmed black man was shot and killed by police, leading to massive protests, and a brutal response from a militarized police force.

Local African-American attorney Charlene Tarver is moderating this weekend's community forum in Phoenix, and we asked her what we could expect out of this forum.

"With the history of shooting involving communities of color, I do believe there will be frustration," she said, but added, "The purpose of the Phoenix town hall is really to talk about solutions."

There was a local protest in response to Brown's killing in Missouri, and local congressional candidate Reverend Jarrett Maupin II cited tension between some communities and Phoenix police that existed before the Cusseaux shooting.

For example, there were protests of Phoenix police after the 2010 killing of resident Daniel Rodriguez by Officer Richard Chrisman, who eventually was sentenced to seven years in prison. At one point, the Phoenix police union held a BBQ fundraiser in support of Chrisman.

"[What's happening in Ferguson] could very well happen here," Maupin said last week. "It's happened here before. It'll happen again until we address the relationships between law enforcement leaders and the community."

UPDATE August 25: DPS with investigate the shooting death of Cusseaux. Click here for more details.

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