The intake area of the new Fourth Avenue Jail can be a tough place to work.

Some of the suspects being booked can be downright hostile toward authority figures. In some cases, the man under arrest is stripped of his clothing and put inside a so-called safe cell -- a lightly padded isolation room -- to cool down.

In more severe cases, devices called restraint chairs are used. They've been criticized by Amnesty International as well as jail consultants hired by the county.

Attorney Michael Manning said, "There are serious questions, nationally, about the safety of these restraint chairs."

At least three inmate deaths in Maricopa County have been linked to the chairs. Two have cost the taxpayers millions of dollars.

Now, 5 Investigates has discovered another death.

Jail surveillance video showed Clint Yarbrough being escorted into the Fourth Avenue Jail on Dec. 21. Less than six hours later, he was carted out on a stretcher with almost no pulse. He died in a hospital later that morning.

There is a lot we do not know about what happened to Yarborough while he was in custody.

We know he was being combative.

Tests showed he had methamphetamine in his system.

Video showed him behaving erratically in his initial holding cell.

We know he was strapped into a restraint chair and booked for assaulting an officer. He was wheeled down the hallway and placed against a wall. Surveillance video showed him rocking in the restraint chair until it tipped over.

A crowd of detention officers gathered around him. Their reports indicate they were trying to gain control of Yarbrough, were forced to use a Taser, and finally had to administer medication meant to calm him down.

At the time, Nathaniel Gatlin was in a cell some six feet away. He told us what he saw looked like a gang beating.

"That's when I was like, 'What are you guys doing? You're beating him to death. You're hurting him.' And he's telling me, they're telling me, 'Shut up, mind your own business.' I'm like, 'Well how can I mind my own business when you're sitting there in front of me, beating the hell out of somebody!?'" Gatlin said.

Manning is representing Yarborough's family in a claim against the sheriff's office. He won suits against the sheriff in two previous restraint chair cases: $8 million in the Scott Norberg case, and $10 million in the Charles Agster case.

Manning believes Yarborough should have been treated medically before being put into the chair.

"They have two medical facilities in that jail - an infirmary and a psych ward. They can help that man. It's equipped to do so. But instead, they just put him in this medieval device and let him sit there strapped in that chair until, in this case, he died," Manning said.

Here's how this could affect people like you:

The county's insurance deductible recently rose from $1 million per case to $5 million per case, meaning taxpayers will now pay five times what they did in the past if the sheriff loses another large lawsuit.

It's something of which county leaders are aware.

Our investigation turned up a stack of audits, memos and court rulings that characterized the restraint chair as a liability. In one report, a consultant hired by the sheriff wrote, "The best recommendation I can professionally make in respect to the restraint chair is to remove it from any use associated with the Maricopa County Sheriff's Office jail." That was May 1997.

As of today, the county and its insurance companies have paid out at least $18 million in jury awards related to the restraint chair. That does not include the latest, the Yarbrough case, which hasn't gone to court yet.

Manning said, "It has cost the county a lot of money. This culture as it exists today is going to cost the county even more money in the future."

Three months ago, 5 Investigates requested an interview with the sheriff regarding this issue. We were told he would not be able talk about it because of litigation.

Thursday night, three hours before our broadcast, the sheriff's office accused us of not giving them an opportunity to react to our investigation.

We have offered to sit down and conduct an interview with anyone from the office who can discuss our findings. If they agree, we will bring that to you in a follow-up story.