Transcript for Baby Clings to Life After Flash-Bang Grenade Lands in His Crib

Imagine the horror of this. Your family asleep in their home, blasted by an explosion. A police S.W.A.T. Team targeting your home, and now a $1 million medical bill for a baby. So, who's going to pay, liter literally? Here's Matt Gutman. Reporter: Buying a Christmas tree -- a cherished tradition during the holidays. Here's our tree. Reporter: But for one family in Wisconsin, struck by tragedy, Christmas seemed out of reach. Enter "20/20." So the family knows that I'm coming, but they have no idea what I'm bringing with me -- desperately needed good cheer. Instead of a sack of toys this year, Alecia and bounkham phonesavnh are stuck with this sack of bills. And this is just part of it. These are just the doctor's bills. Last spring, their house burned down. They sought refuge in Georgia. Two parents and four young children, crammed into garage. They thought they'd finally found refuge until one night last may, when an explosion jolted them out of sleep. I didn't know what was going on. I knew that there had been an explosion. Reporter: At about 2:00 A.M., a fully-armored S.W.A.T. Team rammed down the door looking for a local drug dealer. Instead they found a family with four small children. An officer had thrown in a flash bang grenade to stun those inside. Bou Bou started screaming. Reporter: But it landed in a crib where Alecia's youngest child -- 18-month-old Bou Bou was sleeping. And then my son starts screaming and I just go for him, and the other officer grabs him first and I never even got to see his face. Reporter: Officers whisked Bou Bou away in an ambulance. They told his parents he was fine. I asked, where is he? What happened? Your son just lost a tooth. He's okay. Reporter: Your son just lost a tooth? When they finally arrived at the hospital to take their baby home, a social worker told them the truth. She told me that our son was in the burn trauma unit. And I lost it. Reporter: A flash-bang grenade had blasted a hole in this face and torso. Doctors say Bou Bou might not survive. It seemed like he just kept getting worse every day. I thought I was, we were losing him slowly. Reporter: They kept him in a medically induced coma for over five weeks. It's just not fair. This should never have happened. We should not be sitting here right now. What did my son do to them? Reporter: The S.W.A.T. Team was hunting for this man who, police say, sold meth to a confidential informant outside the home where the family was staying. Problem was, the suspect lived across town. They raided the wrong house. They did not do their job. Toddler burned by a flash grenade. Reporter: Two days later the man in charge of the raid, Habersham county sheriff joey Terrell went public. We just knew there wasn't children in there. We had our minds set on what the game plan was to go in and do it. Reporter: Odd since the phonesavanhs had been there for two months. If they would have done their job at all, any kind of surveillance, they would've known their suspect did not live there and that there were plenty of children in that house. Reporter: According to Alecia, the family's minivan was parked in the driveway with their four car seats in it. With the doors closed, you can see car seats. Reporter: And decals on the back window showing three children and a stroller. So this is the door. This is the actual door right here. Still has the damages. Reporter: Marcus Coleman is a local community activist. So they busted through here. Tossed the grenade in. He took us into the converted garage where the family slept that night, they say, under the glow of a giant flat screen TV they used as a night light. Cartoons were on. I believe they were. Any due diligence of police work before coming in, in such a militarized fashion would've prevented this tragedy. Reporter: So we've come here to Habersham county sheriff's office to try to get some answers from the sheriff himself. Good morning. He's a big man with little to say. I just want to ask you a couple of questions about the phonesavanh family. I can't answer any questions under advice of counsel. Reporter: Clearly there was a tragic mistake. You know not going to get off on tactics with you, not going to get off in the weeds on it. Reporter: Lot of weeds here, huh? There's tons of weeds. Reporter: Have the tactics changed? We've examined everything we do. We've trained with other teams. And there's not going to be a real good answer to that one, is there? Reporter: Since we couldn't find answers in Habersham county, Georgia, we found a S.W.A.T. Team in Florida to demonstrate how to safely deploy a flash bang grenade. Sheriff's office! Search warrant! Reporter: This is what it looks like. There's a time and place for it. We don't use it very often. Reporter: We went back to Georgia, where Habersham district attorney Brian Rickman convened a grand jury to look into the botched raid. But as in the recent cases in Ferguson, Missouri, and Staten island, New York, which sparked protests across the nation, the citizens of Habersham county found no grounds to charge any of the officers involved with a crime. If you are responsible for a flash bang and you deploy that flash bang into a pack-and-play and nearly kill an 18-month-old toddler, how is that not criminally negligent? If we had any evidence that they knew the pack-and-play was there, you're in the criminal sector there. Reporter: Good information, such as a minivan with four car seats right in front of the front door? That's a good point. But once those S.W.A.T. Team guys are out of the car, once that "Point of no return" has passed, it's not criminally negligent for them not to have investigated that van. Reporter: But the Broward swat team says that there's no such thing as a "Point of no return." They can't Deloy a flash bang if there's any sign of children. Have you ever had to not deploy, not throw the device? We'll say, "We're not deploying." And we'll remove ourself from the situation. Reporter: When you deploy it, is it supposed to hit skin or flesh or touch anyone? No. Reporter: Do you think anybody from that swat team did anything wrong? There were mistakes made. The intelligence on the front end, is how the tragedy could have been avoided. Reporter: That intelligence was gathered by a drug unit that was disbanded one day after we rolled into town and confronted sheriff Terrell. And guess who oversees that unit's budget -- sheriff Terrell among others. You're involved, intimately, in the workings of this unit. Seems like a conflict of interest. It's not a legal conflict of interest. Reporter: Four years ago, undercover officers in the same drug unit shot and killed unarmed pastor Jonathan ayers at this gas station. Earlier this year, his pregnant widow was awarded $2.3 million in a wrongful death suit. And guess who convened the grand jury in that case? Were there any criminal charges after the pastor ayers shooting? With respect to the death, there were no criminal charges. Reporter: So, no criminal charges there, and no criminal charges with respect to the phonesavanh case. That's correct. Reporter: Sure is easy for law enforcement to hurt people and get away with it in that area, isn't it? Is that a question, or -- Reporter: Yeah, that's a question. Are there any repercussions for law enforcement officials and officers who are involved in seriously injuring someone or killing them in your jurisdiction? Yes. Reporter: Criminal repercussions. Nobody went to jail. Why can't they just say, you know, "I'm sorry. We've messed up. We're gonna make things right." Reporter: Has the sheriff or anybody from Habersham county ever apologized? No. Reporter: Has anybody ever called you to say, "We're sorry"? We have not received any phone calls. No cards, no teddy bears, no balloons. No, nothing on Bou Bou's behalf at all. Reporter: After nearly six weeks, Bou Bou toddled out of the hospital, with more than $800,000 in medical bills. Which the county refused to pay. Before this we had no debt. We didn't owe anybody anything. And now after all this, you know, they have completely financially crippled us. Reporter: We've decided to crash the Habersham county board of commissioners meeting to try to get some answers from the folks here about why it is that they refuse to pay for any of the family's substantial medical bills. We cornered county manager Phillip Sutton. It is not legal for the county to authorize payments for the medical bills. Reporter: This is a family that nearly lost their son. His face was nearly blown apart. A hole. I can't discuss this anymore. Reporter: The sheriff said "Send the bills to the county." The sheriff can't make a commitment like that. Reporter: The phonesavanhs, buckling under medical bills now topping a million dollars, are planning to sue the county, struggling every day. But today, at least for a few hours, there's some Christmas cheer -- with new toys, a twinkling tree and a little boy, grinning again. So, our question here tonight, who do you think should be responsible for the medical bills? Use #abc2020. And you can find more investigation on our website, abcnews.com. We'll be right back. Next -- they're being naughty. Not nice. Christmas culprits. Stealing presents off your

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