In a news conference on Wednesday, Crump said the autopsy shows Joshua Feast died from a single gunshot wound to the back.
"It is very consistent with literally what the witness' accounts were from that night," said Crump. "When it entered, it caused all kinds of damage and literally the injuries caused Joshua Feast to be dead on arrival at the hospital."
Crump and Feast's family are pressing the police department to release video evidence captured at that time of the 22-year-old's death on Dec. 9.
During Wednesday's news conference and vigil, Feast's family was also joined by other relatives who lost loved ones during encounters with police. George Floyd's brothers and Pamela Turner's daughter were at the event.
Marian Tolan's son, Bobby Tolan, was shot by a Bellaire police officer in 2008. He survived.
"With this case, there's no way they can use, 'I [feared] for my life,'" said Tolan.
In the wake of 22-year-old Feast's death, some of his neighbors in La Marque voiced their displeasure with the town's police department.
SEE MORE: Community in city of La Marque protests after police reveal officer who shot and killed 22-year-old
The officer's name, Jose Santos, was released, but not without hesitation by city leaders. La Marque PD Chief Kirk Jackson became contentious over questions about the officer's age and race, let alone his name, which the chief and Mayor Pro-tem Keith Bell refused to answer. This was despite police immediately identifying Feast as Black.
According to Jackson, the information on Santos was subject to approval by the Galveston County Sheriff's Office, which is leading the investigation.
Jackson also confirmed there was body camera footage of the confrontation, to which he said will be released to the public following the investigation. This is the same footage that Crump and Feast's family wants released immediately.
While exact details of the shooting have been withheld to the public, Feast's family claims he was shot in the back as he was running away. They also claim Santos kicked his body after shooting him.
READ MORE: La Marque man was fatally shot in the back by officer, uncle says
Follow Stefania Okolie on Facebook, Twitter and Instagram.