Accused bus hijacker reportedly off his bipolar meds, doctor weighs in

Loved ones say 39-year-old Joseph Grier was off his bipolar medication for weeks and was in a manic state when he allegedly hijacked a Gwinnett County bus and shot a man on Tuesday afternoon.  

"He’s a different person when he takes that medication," said a family member. "If he doesn’t take his medication, if he doesn’t sleep for a period of time, he starts babbling. We know he’s ready to go off the deep end." 

That's what the family member said has happened these past few weeks.  

SEE ALSO: Gwinnett County Transit Bus hijacking suspect described as 'soft, calm and loving' 

FOX 5's camera captured Grier at the scene of the downtown shooting at Peachtree Center shortly before the hijacking. He told reporters that he was diagnosed with bipolar disorder and hadn't taken his medication in weeks.  

A short time later, cops said he boarded the Gwinnett County transit bus a few blocks away and got into an argument with 58-year-old Ernest Byrd, Jr. Cops say Grier took Byrd’s gun from him, shot him, then told the driver to go. 

RELATED: Wife of hijacked bus driver shares harrowing Atlanta chase experience

Dr. Cecil Bennett, a doctor at Newnan Family Medicine, said he sees it all too frequently among people with mental illness. 

When they stop taking their medication, the worst traits of the illness can come roaring back.  

"You can’t just snap out of it as much if you’re having a heart attack and someone tells you, you need to snap out of it," Bennett said, 

Bennett said the horrifying incident is a snapshot of the mental health crisis in our communities. 

"We have a broken healthcare system especially when it comes to mental health," he said. "We need to make sure that everyone who is in that position that that person was in has immediate access to both medication, that they can afford it, and have access to counseling." 

SEE ALSO:  Gwinnett County Transit Bus hijacking: Victim killed on bus identified

The family member said Grier's father unsuccessfully tried to bring him home earlier in the day.  

"But for the grace of God go our sons or our daughters," he said. "Those families have gone through hell over the years trying to keep this person saying and under control." 

Grier has 19 prior arrests. 

His family says the only good thing about him getting locked up was him getting back on his meds. 

Bennett warns these cases of extreme mental illness won’t go away until access to resources improves. 

"I know he’s probably coming down off of it as soon as they give him some medication," the family member said. "Then he’ll realize what he’s done." 

Joseph Grier's criminal past

During a press conference Tuesday night, Atlanta Police Chief Darin Schierbaum said Grier has had 19 arrests, some of which involved the use of a handgun.

According to the Georgia Department of Corrections, Grier was last released from Baldwin State Prison a decade ago after serving time for a 2011 aggravated assault in Fulton County. In addition to the two counts of aggravated assault, Grier also served time for the possession of a knife during the commission of a crime.

Joseph Grier (Fulton County Sheriff's Office)

The chief said his last known address was in Stone Mountain.

Grier is facing one count of murder, 14 counts of kidnapping, one count of first-degree hijacking a motor vehicle, 13 counts of aggravated assault, possession of a firearm or knife during the commission of or attempt to commit certain felonies, and possession of a firearm by a convicted felon.

Grier waived his first court appearance on Wednesday morning.