Joshua Johnson, 35, was watching a neighbor's home on East Ritter Circle while she was in the hospital.
HCSO said a member of their department who works for the Gulf Coast Task Force was in an unmarked unit staking out a suspect from Dallas County in the area on April 22.
Around 6:00 a.m., officials said Johnson approached the unmarked unit with the flashlight on his phone turned on and a BB gun in his hand. They said words were exchanged, Johnson lowered his flashlight, raised his BB gun at the deputy and the deputy fired at least two shots outside of his window.
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The sheriff's office said the BB gun Johnson had looked like a Glock handgun.
Neither a body camera nor dash camera was used by the deputy in question, according to officials, because he was working undercover.
On the day of the killing, HCSO said Johnson was hit once. An autopsy was performed on the 35-year-old which listed his cause of death as "multiple gunshot wounds."
Since then, a spokesperson for the sheriff's office said the information given on the scene was preliminary.
Johnson's family, alongside Congressman Al Green, held a press briefing on Wednesday morning to discuss the discrepancies they believe exist in the deputy's story.
"It hurts," Wilhelmena Beary, Johnson's mother, said. "I thank God for giving me the inward strength I need to stand, especially today."
A neighbor almost directly across the street found a bullet in his driveway the morning of the shooting, and a mark on his garage where the bullet hit.
Robert Pringle had at least four cars parked in his driveway that day. The mark on his garage is not visible from the street. It is blocked by cars. None of his cars, as far as he can tell, were struck by the bullet.
A member of Johnson's family took a video on their cell phone of the conversation they had with a member of HCSO explaining the facts of the shooting the day it happened. It appears the deputy did not know he was being recorded.
"This investigating officer concluded what the facts were within several hours after Joshua's death, before the medical examiner examined his body, before there was a ballistics report, before there was an autopsy, without questioning the officer who shot Joshua, without the benefit of a body camera and in spite of evidence contradicting his version of the facts," Congressman Green said.
Congressman Green said Wednesday that he had not reached out to the sheriff's office to voice his concerns.
Johnson's parents believe their son might have been killed in a case of mistaken identity. They believe it's possible he was mistaken for the capital murder suspect the Gulf Coast Task Force was looking for at the time.
When asked about that possibility, HCSO said they could not answer because the case is under investigation.
They issued the following statement:
"Separate investigations into the April 22 shooting death of Joshua Johnson are being conducted by the Harris County Sheriff's Office Homicide and Internal Affairs bureaus, as well as the Harris County District Attorney's Office. Once these investigations are complete, the findings of these separate investigations, along with the autopsy findings of the Harris County Institute of Forensic Sciences, will be presented to an independent grand jury to determine whether criminal charges are appropriate. Our condolences go out to Mr. Johnson's family for the loss of their loved one in this tragic incident."
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