Smyth was receiving care near Charleston when impending Hurricane Irma forced him to be evacuated to Columbia.
Video from inside the VA facility shows Smyth entering a room with other patients.
Then seconds later, there was an altercation, and medical staff rushed in.
Two men immediately tackled Smyth to the ground, and one could be seen putting him in a headlock.
"He is pressed flat on this floor with someone who has their arm around his throat, pressing on his carotid (artery)," said Randy Hood, an attorney for Smyth's family. "Another person is on his back pressing his belly into the floor, which means it is going up into his body cavity and pressing on his diaphragm. That's how we breathe."
Hood said Smyth's family is devastated and outraged by what happened next.
The video shows VA employees restrained Smyth at 2:39 p.m.
At 2:49 p.m., an employee checked for a pulse, and less than a minute later, they began CPR.
The Navy veteran did not survive.
The coroner's report lists his manner of death as a homicide.
"No one was charged with a crime, none, zero, zip," said Hood. "A homicide and no one was charged.
Who is going to be held accountable?"
Smyth's family filed a civil lawsuit against the United States over their son's death.
Jeremy Butler is a Navy veteran and CEO of a veterans' advocacy organization, Iraq and Afghanistan Veterans of America.
"I am incredibly angry," said Butler. "This is a veteran who turned to the group that is supposed to be taking care of veterans, to the VA, and that is where all of our veterans should feel safe turning to for help."
Butler said Smyth's death is a horrific example of the lack of adequate mental health care veterans nationwide.
"We are already at 20 a day dying by suicide. We have a hugely unmet mental health crisis that's going on in the veteran community," said Butler.
Concerns over veterans' care go beyond mental health.
In Arkansas, a former VA doctor, Robert Levy, faces involuntary manslaughter charges.
The pathologist is accused of entering false test results contributing to the deaths of three men.
In West Virginia, the FBI is investigating 11 suspicious deaths. One veteran's family claims he died of a fatal dose of insulin.
In August in Salisbury, WSOC-TV reported that Dr. Gregory Earl Scott got his license back after losing it for seeing a patient while intoxicated.
Veterans advocates said there must be change so that our country's heroes are treated with honor.
"We're going to continue to work with the VA, to work with Congress, to work with other veterans service organizations to make sure that what Luke Smyth went through, no other veteran needs to go through," said Butler.
Anchor Allison Latos contacted the VA.
A spokesperson said they don't comment on litigation but provided a statement saying: "Thousands of South Carolina veterans choose to be treated at the Columbia VA Health Care System. In addition to operating one of the largest and most complex facilities in the nation, the facility maintains combined inpatient and outpatient quality standards that are in the top 15% of the nation."
Latos also reached out to the solicitor's office to explain this case.
An employee said the office has had staff changes since 2017, and they could not immediately answer WSOC-TV's questions.
Latos has also reached back out to the VA.