A 6-month-old baby died in Dallas after his baby sitter's repeated calls to 911 went unanswered. (Reuters)

Since November of last year, Dallas officials and cellphone provider T-Mobile have known that a mysterious technology glitch was wreaking havoc on the efficiency of the city’s 911 call center, tripping “ghost calls” to dispatchers and placing legitimate callers on hold for unsafe spurts of time.

In January, they thought it was fixed.

But by March, operators were once again slammed with an unprecedented backlog spike that prompted the city manager to write in a memo that at one point on March 6, there were 360 emergency calls on hold.

Only days later, that record was dwarfed by a new one: 442 callers placed on hold for an average of 38 minutes.

Yet it wasn’t until Tuesday, when a mother said the problem had led to the death of her 6-month-old baby, that officials from the city and T-Mobile jumped into action. Dallas Mayor Mike Rawlings said in a statement that it was “outrageous” T-Mobile had not yet resolved the glitch, and by Wednesday morning the company’s executive vice president and a team of top engineers were in Texas investigating.

To reassure the public, the parties called a news conference later Wednesday, which yielded few direct solutions to the problem and, within minutes, led to a suggestion that another death might be related to the 911 problem.

David Taffet, a local blogger, was among the first reporters at the news conference to ask a question, revealing that on March 6 — the day 360 emergency callers were on hold — it took 20 minutes for a dispatcher to answer his own plea for help.

He had come home that day to find his husband, Brian Cross, disoriented. The 52-year-old had lain down and was snoring, Cross wrote at Dallas Voice. Then suddenly he wasn’t. Taffet called 911 but after a few minutes was disconnected. No 911 operator called back, as protocol requires. Taffet tried again but had to wait 20 minutes for an answer.

“By that time, no matter how much I breathed into his mouth and pounded his chest,” Taffet wrote, “Brian wasn’t breathing.”

At the news conference, Taffet asked the mayor: “How many others have died?”

The mayor had no answer, but shared with Taffet the same condolences he gave Bridget Alex, the mother of the 6-month-old baby: “My heart is broken for the loss of a loved one, and I’m sorry for you as well,” the mayor said. “We’re going to get to the bottom of this. I promised her that, and I promise you this.”

Asked why it took the death of a child to get some action, Rawlings responded: “I don’t know. I’m very disappointed with that.”

He said something should have been done weeks ago, but that officials were “looking ahead.”

“We’ve got them here now,” Rawlings said of the engineers.

The technology glitch works like this: When T-Mobile customers call 911, their phones — for reasons still unknown to officials — repeatedly call 911 while they sit on hold. Those calls register as hang-ups, forcing operators to return each hang-up call to verify if there is a legitimate emergency.

The manual callbacks further clog the call line.

David Carey, T-Mobile executive vice president, said his team met Wednesday with city officials but “didn’t get through all the solutions.” The company’s immediate advice for citizens, Carey said, is to resist the urge to hang up the call if they are put on hold because calling multiple times makes the problem worse.

Carey said one immediate solution is to manage the “supply and demand” by increasing call center staffing when volume spikes and changing the call waiting announcement to encourage those seeking help to remain on the line despite the response delay.

“We will stay on this until it is fully resolved and everybody can rest comfortably that when they call 911, their call and emergency request for help will be addressed immediately,” Carey said.

The city plans to have police officers with dispatch experience work overtime at the 911 call center this week and offer training to other city personnel who are willing to help out.

“The last thing you want to experience when you call 911 is to be placed on hold,” said city manager T.C. Broadnax, “so our goal ultimately is to try to reduce anyone being on hold, but when they are, we want to limit that time and we want to be able to be responsive.”

It’s unclear whether the deaths of Taffet’s husband or Alex’s baby, named Brandon, could have been prevented by more prompt medical attention.

Taffet told the Dallas Morning News he is waiting for officials to determine a cause of death. The Dallas Police Department and child protective services are investigating the death of Brandon.

The infant’s mother told local news that her son’s babysitter, who is also his godmother and a family friend, first called 911 when he fell off a daybed and was barely breathing.

But the call, which should have been answered by dispatchers in Dallas within seconds, just rang and rang and rang.

When nobody answered, she hung up and called back, but was put on hold for nine minutes, Alex told the Dallas Morning News. So she hung up and called back again, but this time reportedly waited on hold for 30 minutes.

She performed intermittent CPR on the boy, Alex said, but couldn’t take him to the hospital because she had no car.

Eventually the sitter called Alex, who was at a funeral for her nephew across town. She rushed home and drove Brandon to the hospital, but it was too late.

At 7:48 p.m., the baby was pronounced dead.

“I want them to take responsibility of my son’s death. That’s what I want them to do,” Alex told the Morning News. “Because at the end of the day, my son was still breathing, but had y’all come out like y’all were supposed to, my son would still be here in my arms. But because you didn’t, my son is gone and I have to bury him on Monday.”

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