The family of fallen Chicago police officer Krystal Rivera is demanding full transparency and an independent investigation, after she was accidentally shot to death by her partner during a foot chase last month.

Rivera's family watched some of the body camera video showing the shooting of their loved one, but their attorney said they were all left with more questions than answers after seeing it.

"I'm asking for complete transparency," Rivera's mother, Yolanda, said through tears on Wednesday, expressing her deep desire for a thorough investigation into the shooting death of her daughter. "I need to understand what happened that night. I need to know the truth."

Police have said the 36-year-old single mother was accidentally shot and killed by her partner on the night of June 5.

"Krystal was a devoted mother to her 11-year-old daughter, and a dedicated public servant. She graduated from the police academy in 2021, and spent the last four years serving with pride and compassion on the 6th district tac team," her mother said.

Rivera was part of a tactical team that had done an investigatory stop. She and her partner chased an armed suspect into an apartment building in Chatham.

When Rivera and her partner approached that suspect, a second suspect confronted them armed with a rifle, according to police.

Rivera family attorney Antonio Romanucci said the body camera footage shown to the family raised more questions for them than answers.

"What's been reported is that somebody got in between the shooter and Krystal, right? Okay. That is something that we do not accept as accurate," he said.

Romanucci also said, with nearly a month passing since the shooting, more information about the case should have been released by now, including video footage.

"It is unusual, because I pose the question that had this bullet come from a civilian's gun, we'd have a lot more answers. The narrative would be a lot clearer. We would know why charges were being filed, why it happened, how it happened, where they were standing," he said. "That's not happening here, and that's why we can't accept the smell test yet, because we're not getting what we should be getting if this had happened in a circumstance where a civilian had shot the gun."

The Rivera family's attorneys sent a letter to Chicago Police Supt. Larry Snelling on June 27, asking for an independent investigation into Rivera's death by Illinois State Police, the release of all unedited body and dashboard camera footage, and the full personnel file of the officer who fired the shot that took Rivera's life.

CBS News Chicago Investigators found at least 10 complaints have been filed against Rivera's partner since he was hired in 2021. 

"We believe the warning signs were there for years," Romanucci said.

When asked for comment, Chicago police said the Civilian Office of Police Accountability investigation into Rivera's death remains active, and the officer involved will remain on administrative duties.

CBS News Chicago is not naming Rivera's partner because he has not been charged with a crime in this case.