A Maricopa County grand jury has indicted a Phoenix police officer on a second-degree murder charge in the shooting of an unarmed man in south Phoenix on Oct. 5.

Officer Richard Chrisman was also charged with aggravated assault with a deadly weapon and cruelty to animals.

Interim Maricopa County Attorney Rick Romley and Phoenix Public Safety Manager Jack Harris announced the indictment at a news conference Thursday.

"I sincerely believe in these good men and women, and I believe that their example epitomizes all that is good about public safety in our communities today," Romley said. "But we as citizens put our trust and our lives in their hands, and when one abuses and violates that trust, we must hold them accountable to the community for that breach."

When asked why it took more than a week to obtain the murder charges, Harris said, "We make decisions based on the facts of the investigation, not rumors, not people being upset. We base them on facts."

Harris said he understood outrage in the community over the shooting of Frank Rodriguez, 29.

"I think the community should be angry," Harris said. "They should be upset. If it were my neighbor, I would be angry as well."

Later in the day, Elvira Fernandez, Rodriguez's mother, said at a separate news conference at her lawyer's office that when she heard about the new charges against Chrisman, "I thought, finally, thank God somebody heard us."

Fernandez said her son "didn't even know I called 911. I was emotional. I thought the police would have a talk with him. I told them, 'Don't hurt my son, just talk to him.' "

She said she heard "banging on the door when they broke it down and I heard my son screaming."

Harris said that he would meet with Chrisman next week to initiate termination procedures against the officer.

Harris and Romley also released information about Chrisman that placed him on the "Brady" list, named for a court case regarding police officers who had committed acts that called their judgment into question.

In 2005, Chrisman was one of four police officers caught on surveillance video planting a drug pipe on a mentally challenged homeless woman as a joke. In the video, Chrisman can be seen placing something in the hand of a police officer who then pretends to take it out of the woman's dress. The woman was not charged with drug offenses.

Watch the surveillance video

Chrisman was disciplined and suspended for one day. His name remained on the Brady list.

Craig Mehrens, Chrisman's attorney, said the videotaped incident "has nothing to do with (Chrisman's) use of force. Rick is selectively releasing things to bolster his case."

Shortly after noon on Oct. 5, Chrisman, 36, and Officer Sergio Virgillo went to the south Phoenix trailer home of Rodriguez's mother. Fernandez had called 911 because she had been arguing with Rodriguez and she was afraid he would assault her.

Rodriguez asked to see a warrant when the officers entered the home, and Chrisman reportedly put his gun to Rodriguez's head and told him he didn't need a warrant, according to court documents. The documents went on to say that both officers fired their stun guns against Rodriguez. Then Chrisman sprayed him with pepper spray and shot a young dog barking in the living room.

Virgillo told investigators the dog was not threatening them and he saw no reason why Chrisman would shoot it. The suspect asked why Chrisman had shot his dog, and Virgillo said he tried to calm Rodriguez down and talk him into coming outside.

Rodriguez told the officers he was leaving with his bicycle, but Virgillo moved to block the door and Chrisman began struggling with Rodriguez over the handlebars.

Chrisman then reportedly pulled out his handgun and shot Rodriguez more than once. Rodriguez died at the scene.

Chrisman was arrested about five hours after the shooting and was freed on bail. He was not rearrested after the indictment.

Mehrens, who successfully defended a Chandler police officer who shot a woman to death at a pharmacy drive-up window in 2002, claims that the Rodriguez shooting was justified.

Mehrens sent a letter to Deputy County Attorney Juan Martinez, who will handle the Chrisman case, asking him to consider the opinion of an expert on police officer use of force.

"Nobody called for my expert's opinion," Mehrens told The Arizona Republic. "You mean the prosecutor is not supposed to look at both sides? I'd have a great case with a fair prosecutor."

Attorneys for Rodriguez's parents attended Thursday morning's news conference. Michael Manning, who represents Rodriguez's father, said he and the father were pleased by Chrisman's indictment, calling the inquiry into the shooting "a brave and courageous investigation."

Hispanic community activist Lydia Guzman said, "I'm pleased to see that the police department has been transparent in every stage of the investigation. I appreciate the police officer who came forward and I worry about any retaliation he may suffer."

Reporter Brealyn Nenes and the Associated Press contributed to this article.