The married Alabama nurse who was shot dead in the parking lot after finishing her hospital shift was on the phone with her husband as she pleaded to not be gunned down, according to a new lawsuit.

Ada Doss, 27, was allegedly killed by Matthew James Taylor, 41, on May 12 as she finished her shift at the DCH Regional Medical Center in Tuscaloosa.

Ada was talking to her spouse, Andrew Doss, as she walked to her car in the hospital's south parking lot before Taylor allegedly killed her, according to a complaint filed Wednesday in Tuscaloosa County Circuit Court viewed by the Daily Mail.

They were talking about their work days, dinner plans and routines for their six–month–old and two–year–old daughters, per the complaint.

Once Taylor approached her with a gun, Ada's voice 'filled with fear and panic,' according to the legal filing.

'Please don't, I have babies,' Ada allegedly pleaded only seconds before she was killed in the parking lot, per the complaint.

Taylor was taken to the hospital's emergency room earlier in the day by an 'unidentified individual' who complained of a manic episode, the wrongful death suit said.

He was allegedly allowed to leave the ER and freely roam around while being unsupervised for hours despite being shirtless, shoeless, and armed, the filing added.

The lawsuit, filed by Ada's husband, claimed that security personnel at the hospital failed to track Taylor down even after being told of his alleged manic and erratic behavior.

However, they allegedly 'failed to assess the security threat' and never even attempted to find or locate him.

Ada was a registered nurse at the DCH Healthcare Authority working at their Tuscaloosa campus.

She was 'devoting her life to providing healthcare to the patients' before Taylor allegedly killed her, the complaint read.

The lawsuit was filed against DCH and Allied Universal Security Services, who the hospital's security personnel belonged to, as well as Taylor.

Andrew claimed that the three had effectively combined to cause his wife Ada's tragic death last month, according to the complaint.

Captain Jack Kennedy of the Tuscaloosa County Sheriff's Office's violent crimes unit previously said that Taylor had 'loitered on and about the DCH campus for several hours,' according to WBRC.

Taylor also tried to rob a woman who was inside her car with a gun, demanding that she get out of the vehicle, according to the outlet.

However, the woman was able to drive away, and Taylor subsequently would have allegedly turned his attention to Ada.

Taylor allegedly tried to steal Doss' purse and, after shooting her dead, went through it, took her keys, and also attempted to take her car.

Tuscaloosa police said Taylor was still armed and just feet away from Doss's body when he was arrested.

He was showing signs of mental illness, police added. He had never met Ada before allegedly shooting her dead in the parking lot.

Taylor now faces capital murder charges. He has been held at the Tuscaloosa County Jail since the day he allegedly killed Doss.

However, a separate lawsuit filed last Friday in the Tuscaloosa County Circuit Court viewed by the Daily Mail claimed that he suffered from 'serious mental illness' and was mentally disabled.

The suit was filed against the DCH Health Care Authority by Taylor's mother, Amanda Taylor.

Taylor allegedly had a history of mental illness since childhood and had been in and out of mental institutions during his entire life, per the suit.

That included facilities owned and operated by DCH, according to the lawsuit filed by his mom.

On the day that he allegedly shot Ada dead, Taylor had experienced an 'acute and severe mental health crisis.'

He was showing serious signs of confusion and irrational behavior, per the suit.

It claimed that 'family members and/or friends' had taken Taylor to the Tuscaloosa hospital to get him emergency psychiatric treatment.

Despite that, the hospital allegedly 'refused' to admit Taylor, per the filing.

He allegedly stayed 'on or near' the hospital for several hours afterwards while 'in the throes of a severe psychiatric crisis.'

It was during that time that Taylor allegedly shot Ada dead in the DCH parking lot.

She was described as a 'beloved nurse, wife, and mother' in the complaint.

The filing claimed that Taylor had 'obtained an improperly secured firearm' to carry out the killing, though it did not mention how.

Allied Universal Security Services told the Daily Mail on Thursday morning that it did not comment on pending litigation. 

The Daily Mail has reached out to Andrew Doss' attorneys, Paul Peterson II and Randy Dempsey, and Taylor's attorney, J. Michael Comer, as well as the DCH Health Care Authority, for comment.