"I think it sends a strong message out to the community that the Dallas Police Department now has taken steps in the right direction with making that decision to fire this officer", said Daryl Washington, an attorney for Jean's family.
The Dallas County District Attorney's Office have requested three warrants for security footage that monitors the townhouses near the apartment where Officer Amber Guyger, 30, shot and killed 26-year-old Botham Jean.
In her arrest affadavit, Guyger told investigators she mistook Jean's apartment for her own and thought she was being burglarized. Jean died at a local hospital.
The Associated Press reports that Dallas has let Guyger go, citing the allegations against her, following an internal investigation into Guyger's behavior.
Guyger was arrested three days after the incident after the Texas Rangers chose to postpone pursuing a warrant "until they could follow up on information that they received from the interview with the officer". She posted a $300,000 bond and was quickly released. Renee Hall did not want to make a statement on Guyger's termination last week because it could cause issues with the investigation.
Neither document specifically states how close Ms Guyger was to Mr Jean when she shot him. The swift termination of any officer who engages in misconduct that leads to the loss of innocent life is essential if the Dallas Police Department is to gain and maintain the public trust.
The search warrant statement says Mr Jean "confronted the officer at the door".
When she put her key in the apartment door, which was unlocked and slightly ajar, it opened, the affidavit said.
She drew her weapon and fired, killing Jean, an employee of accounting firm PricewaterhouseCooper.
Guyger had been with the department since November 2013. That position apparently changed over the weekend, as Guyger's firing was not expected.
S. Lee Merritt, an attorney for the Jean family, said the police chief informed the family of the department's decision on Sunday night and they supported the move.