Amber Guyger's defense team is appealing her conviction last year, claiming the charge should have been criminally negligent homicide instead of murder.
The lesser charge would possibly mean Guyger could be released on parole.
"I feel furious about it," Botham Jean's mother Allison said in an interview from her home in St. Lucia. "It really made me question the nerve of Amber Guyger and her attorneys to even think of wanting to file an appeal."
Guyger, a former Dallas police officer, was sentenced to 10 years in prison for shooting and killing Botham Jean inside his apartment in September 2018.
Guyger also lived in the same apartment complex, one floor directly below Jean, and said she mistook him for an intruder when she entered his apartment instead of her own.
Jean's mother said if the case is reconsidered, Guyger should get life in prison.
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"How can you kill someone in the comfort of their home and just say, 'I'm sorry," Allison Jean said. "An apology and you get away with it? I mean where in the world does that happen."
During a frantic call to 911 following the shooting, Guyger told the operator over and over that she thought she was in her apartment.
Murder "requires evidence beyond a reasonable doubt that the defendant intentionally or knowingly caused the death of the complainant," Guyger's lawyers said.
While the defense argues that Guyger did knowingly shoot to kill, she believed that her life was in danger and so she was entitled to use deadly force.
Guyger's defense attorneys said the lack of obvious floor markings and identical layouts for each floor often led to confusion among residents about which floor of the building they were on.
Guyger lived in the same apartment one floor below Jean's.
"Apartments 1378 and 1478 had the same floor plan and the kitchen, countertops, couches and televisions were all in the same places," the defense said in the appellate brief.
Additionally, the doors had locks that used an electronic key for access and did not automatically lock when closed. Jean's door was unlocked, allowing Guyger to enter even after inserting her fob into the door, they said.
In the trial last fall, several residents of the apartment building testified that people had accidentally walked into their unlocked apartment after becoming confused. In the appeal, defense attorneys said they interviewed 297 out of 349 residents of the building and that 23% of the tenants on floors three and four had gone to the wrong door and inserted their fob into the locks.
They also added that 71 tenants said they had walked into the wrong apartment on the wrong floor and that 76 tenants who lived on the third or fourth floor had unintentionally parked on the wrong floor.
Russell Wilson, a defense attorney who is not associated with the case, told NBC 5 on Friday that he wasn't surprised to see Guyger's appeal filed and that it's common and expected for convicted people to file appeals. However, it is possible for a defendant to waive their right to an appeal.
Wilson, who spent time with the Dallas District Attorney's Conviction Integrity Unit, said what will happen next is the state will have an opportunity to file a written response to the brief and the defense will be able to file a reply. Then the court of appeals would take up the issues in the briefs and a three-member panel will render a written opinion on whether she'll be convicted of the lesser charge.
Filing the appeal, Wilson said, was a no-loss proposition for Guyger either way.
That's because her defense asked for her to be acquitted and convicted of a lesser charge, not to be retried for the murder.
For the murder conviction, Guyger faced between five and 99 years but only received 10 years behind bars. If she asked for a new trial and was again found guilty of murder, she may be given a longer sentence.
“By asking for the negligent homicide conviction you’re able to ensure that any sentence you get would not be more than the ten-year sentence that you already have,” said Wilson.
With the criminally negligent homicide conviction, however, Guyger would face 180 days to two years behind bars. According to Texas law, if a deadly weapon is used, the charge is then a third-degree felony punishable by a maximum 10 years behind bars.
Probation does remain an option with a negligent homicide conviction, the defense said. So even with the third-degree negligent homicide conviction, the best case for Guyger could be probation or time served.
Wilson added the overwhelming majority of appeals lose, estimating fewer than five percent are granted, and that it could be sometime next year before that opinion is handed down.
“If you’re just saying, ‘What are the odds’ here?' The odds are against the person who is appealing,” Wilson said. “That being said each case is going to be taken on a case by case basis.”
Attorney Mowla did not respond to a request for comment.
The Dallas police department declined to issue a statement on the appeal.
"Since Amber Guyger is no longer employed by the Dallas Police Department, we are not going to provide a response," a spokesperson said.
Allison Jean said she and her husband marked their 31st wedding anniversary Friday but there was no celebration -- even as others call to congratulate them.
"The one call I cannot get is from my son," she said. "I'm in pain. It's hurting."
