Cardan Spencer and Amy Wilburn were both charged with aggravated assault by a public servant.
Spencer was indicted last week after shooting a 52-year-old man standing several feet away from him. A police report filed in the case initially claimed the man, Bobby Bennett, lunged at Spencer with a knife.
A neighbor's surveillance video camera captured a recording that showed Bennett was several feet from the officers and didn't appear to move toward them before gunfire caused him to crumple to the ground. Bennett was hospitalized for several weeks following the October incident.
Bennett's mother, Joyce Jackson, said last year that her son had been diagnosed with schizophrenia and bipolar disorder, and that he was off his medication at the time of the shooting.
Spencer's indictment last week followed the indictment of former officer Amy Wilburn, who was charged after shooting a 19-year-old suspected carjacker.
Dallas police fired both officers shortly after the separate incidents. Police Chief David Brown has suggested an expansion of the use of body cameras to avoid relying solely on officers' statements in disputed situations, and the department reiterated that its use of force policy gave police officers "a responsibility to use only the degree of force necessary to protect and preserve life."
But police union leader Ron Pinkston said the indictments are a bad signal to send to officers dealing with potentially life-threatening situations.
"The result will be more names on the police memorial wall," he said.
In both cases, the existence of recordings brought the officers' actions into question. But Pinkston said the video alone could be misleading and that police work is not always clear.
"The video is just one part of the investigation," he said. "But that's not what the public sees. They only see the video and they make conclusions off the one piece of evidence."
Brown said in an emailed statement Monday said that he was committed to "the safety and security of each Dallas police officer" as well as city residents, and that the department would maintain training standards to help officers.