Updated

A Dallas police officer's explanation that she killed a black neighbor who lived above her because she mistook his apartment for her own has been dismissed as implausible and self-serving by his family and their lawyers.

But experts on police training and psychologists are split on the credibility of Officer Amber Guyger's story.

Guyger's credibility will be key to whether a grand jury will indict her and whether she could persuade a trial jury that the killing of Botham Jean was tragic, but justifiable.

Some experts who aren't connected to the case say Guyger should have recognized what was really going on and stopped short of using deadly force.

Others say that even though Guyger was in the wrong apartment, she could have had a reasonable belief that she was defending her life and her property.