Family demands $10million from Tennessee county after mom, 35, died handcuffed in the back of new deputy's cruiser when he got lost and drove into a river moments after making his first-ever arrest

The family of a Tennessee woman who was found dead in the backseat of a submerged police patrol car are now suing Meigs County for $10million following the tragedy. 

Meigs County Sheriff's Deputy Robert 'RJ' Leonard who had only been on the beat for less than two months, arrested 35-year-old Tabitha Smith after responding to a report of a man and a woman fighting on a bridge around 10pm one February night.

For Leonard, who only joined the police department following 12 weeks of training, it  was the new deputy's first-ever solo arrest. 

But the deputy's vehicle plowed into the Tennessee River after he took a wrong turn drowning the both of them.

A lawsuit was has now been filed by Smith's son Nathan, on his mother's behalf.

Tabitha Smith, 35, was found dead in the backseat of a submerged police patrol vehicle 

Smith's remains were discovered in the backseat of a police patrol car, shortly before the body of the missing deputy was also recovered from the Tennessee River

Deputy Leonard 'was not properly trained by the County to know his assigned area of patrol and know the nature of the incident location,' the suit alleges before stating how Leonard 'was not properly trained or supervised by the County to refrain from the use of his cell phone while transporting an arrestee in a patrol vehicle.'

Minutes before the fatal plunge, Leonard had texted his wife about the arrest to which she had responded, 'that's great' - although the deputy never received her response.

Leonard had made a final call to his dispatch saying 'water,' before losing all communication with the office. 

Smith was still handcuffed in the back seat and unable to free herself as the icy waters of the river rushed into the car.

The following day, Leonard's patrol car was pulled out of the Tennessee River, and Smith's body was recovered from the vehicle. Leonard's body was found hours later nearby.

Robert 'RJ' Leonard, a deputy with the Meigs County Sheriff's Office, made a chilling call to dispatch, saying 'water,' before subsequently losing communication with the office

The family of Tabitha Smith are suing the county for $10million in damaged following her death

 Leonard's patrol car was pulled from the Tennessee River with Smith still cuffed in the back 

The deputy's car is seen being towed away after being dragged out of the Tennessee River 

Deputy Leonard was unfamiliar with the roads close to the river and drove off a boat ramp straight into the water and was unable to escape 

'Leonard was not properly trained or supervised by the County to ensure the safety of the Deceased while in his custody,' the lawsuit alleges noting how Smith likely 'suffered a horrific death.'

The lawsuit claims the deprivation of liberty interest and bodily integrity, wrongful death, battery and assault claims, intentional infliction of emotional distress, gross negligence, loss of consortium and two violations of Tennessee code.

Deputy Leonard had graduated from the training academy in December last year and joined the force. 

'Deputy Leonard had only been here for a couple of months, but he had become a part our family,' Chief Deputy Brian Malone said in tears at a press conference last month. 

'It's a hard time for us here. It's something that we don't ever deal with here in Meigs County,' he added. 

'Deputy Leonard had only been here for a couple of months but he had become a part our family,' Chief Deputy Brian Malone said in tears during a February press conference

In his final radio call, Leonard said 'water,' a word that authorities had to use 'special techniques' to decipher later. 

'Dispatch couldn't tell what he was saying,' Johnson said. 'We think he was saying, "Water."'

A satellite tracking of his vehicle and a location sharing app on his phone led the officers to Blythe Ferry Road near the Tennessee River. 

'They triangulated the last position of his phone and the Life360 that his wife has attached to his phone, and it appears that they're almost in the same location,' Johnson said. 

When the vehicle was found it was upside down with the wheels up, The driver-side window was also down. 

Johnson said the deputy appeared to have been texting and talking on the radio while driving on a treacherous road. 

'The roads are not well lit. They are not well marked. They are narrow. If he was not paying attention, he could have hit that water pretty quick,' Johnson said. 

The deputy graduated from the training academy in December and then joined the force

The devastating incident has left Leonard's wife and children in anguish, as his wife shared in a social media post

'We're operating under the theory that it was an accident - he missed his turn, he wasn't familiar, and he was doing other things that may have caused him to go into the water,' Johnson said. 

The devastating incident has left Leonard's wife and children in anguish, as his wife shared in a social media post. 

'Our lives are forever changed. Please just keep praying. Pray harder than you ever have before. My heart is breaking for my kids, and I am just an absolute wreck. I will start reaching out when I can pull it together. 

'For now, all I can do is cry. We love you forever RJ. 17 years isn't long enough with you,' she wrote.