Major update in death of teen killed by spoiled friend Kiernan Tague who was speeding in BMW - as cops request warrant for 'family member' of boy behind the wheel

Michigan officials have requested a warrant for a relative of a teen accused of killing an 18-year-old star swimmer in a horror crash - as the victim's parents demand the driver's mom be held accountable for the tragedy.

Flynn MacKrell was killed instantly last November when then-16-year-old Kiernan Tague lost control of his mother's BMW while going over 100mp in a 25mph residential zone in Grosse Pointe.

The MacKrells say their son's death could have been prevented by Kiernan's mother Elizabeth Puleo-Tague, a campus minister at a Jesuit high school who allegedly knew Kiernan had a speeding habit but failed to keep him away from her BMW.

The Wayne County prosecutor's office told DailyMail.com on Wednesday that Gross Pointe police has requested a warrant for a relative of Kiernan, though they could not confirm that it was for his mother Elizabeth.

'He had no regards for his passenger's safety, no regard for pedestrian safety, and the mother knew it,' Flynn's father Thad Mackrell told Good Morning America on Wednesday. 

'Any reasonable person would have done something very, very simple - they would have taken the keys away, and she didn't do it, and our son is dead.'

Kiernan has been charged with second degree murder over his friend's death, but the MacKrells say they want his mother held responsible, too. 

'Every day we wake up in shock and disbelief that our beloved Flynn is gone,' said the star swimmer's heartbroken mother Anne Vanker.

The MacKrells are pointing to the case of Oxford shooter Ethan Crumbley, whose parents were convicted of involuntary manslaughter in a landmark case earlier this year for providing the gun that he used to kill four people.

Kiernan lost control of the vehicle just five minutes later while traveling at 105mph, hitting a pole and then a tree. The force of the impact obliterated his mother's BMW X3 M and killed Flynn, a standout swimmer at the University of Dayton. 

Kiernan escaped with his life but is now out on bond awaiting trial after being charged with second-degree murder in March. His trial is set for February, 2025.

DailyMail.com has reached out to Elizabeth for comment on this story. 

Elizabeth's employer, University of Detroit Jesuit High School and Academy refused to comment when reached by DailyMail.com on Wednesday.

As previously reported, Elizabeth is being investigated by police after text messages emerged showing she was aware of her son's speeding habit - which she had intimate knowledge of through a GPS app called Life360. 

Flynn's parents previously told The Detroit Free Press that Elizabeth should face criminal charges, with his devastated mother Anne stating: 'It's like she handed him an AR-15.'

Among the text messages, Elizabeth wrote to Kiernan on September 14, 2023, two months before the crash: 'Slow the f*** down right now!'

It was after the then 16-year-old had been caught traveling 123mph in the family's Audi coupe.

'I have screen shots of you... doing 123 mph... It scares me to my bone,' read another.

Flynn's parents, Anne Vanker and Thad Mackrell, are seeking to use the messages to show how Elizabeth failed to take reasonable actions to prevent her child from hurting others.

They wrote in a letter to local prosecutors: '[Kiernan] was speeding over and over, and mom knew it'.

Not only that, but Elizabeth, the campus minister at a local Catholic School, bought herself a brand-new BMW weeks after sending those texts that she proceeded to give her son access to, despite it being able to reach speeds of 177mph.

Kiernan had a history of bad behavior aside from speeding, including assaulting his mother in 2020.

The offenses were uncovered by Grosse Pointe City police officers who penned a report laying out the more than 20 offenses, and problems he was having at home before he took the BMW out for its fateful final ride while mom was away in Canada.

Citing the 'extensive' text messages between the two compiled during this effort, one investigator wrote: 'There was much conversation about Kiernan taking/using his mother's credit card without permission, being out during overnight hours without permission, and about Kiernan's extensive reckless driving habits.'

The investigator added: 'The messages between the two suggest that Kiernan's mother has little to no control over Kiernan.

'Kiernan regularly drove recklessly and took/used his mother's credit cards without permission, despite his mother's repeated orders not to.'

Another exchange cited was a text from the mother to her 16-year-old son on October 2, 2023, a little over a month away from the crash.

It read: 'Will you pick up a bottle of wine?? … Please!' to which Kiernan replied, 'Sure.'

A week later, his mother sent him a screenshot of a website laying out the penalties for having a fake ID.

In 2020, police responded to a call from the mom after she alleged her son 'had just assaulted her and fled the area,' cops wrote.

The report goes on state how the incident occurred - when Kiernan was being picked up at his friend's house and became angry at his mother.

'While in the front seat, Kiernan turned around and began punching his mother (who was in the back seat) and even bit her on her hand,' an officer wrote.

Kiernan, in turn, was arrested for domestic violence and kept briefly at the Wayne County youth home.

In November of last year, days before the crash, another fight would break out between the two, this time at home, during which Kiernan broke a table after his mom refused to let him use one of her two cars.

'I simply asked you to take your car... yet you refused. Now I'm running late and we have a broken table,' Kiernan texted on Nov. 3, 2023, according to the report viewed by the Free Press.

He also apologized: 'I'm sorry about your table.'

Within two weeks, the crash occurred - as cops wrote the majority of the calls they received about Kiernan involved complaints of him being out of control at home.

'His mother repeatedly told responding officers that she was afraid of Kiernan,' an investigator wrote, adding their most recent to the family's home was on August 30 of last year.

The reason for the visit was 'because [Kiernan] was yelling and throwing items within the house because his mother refused to get him an American Express Gold Card.'

The Mackrells are now using the exchanges between the mother and son as proof Elizabeth knew for months her son was driving recklessly, but failed to do anything about it.

Speaking to the Free Press, she brought up how Elizabeth also has a 2015 Subaru Forrester, but continued to allow her son to drive the much more powerful Audi and then BMW even after warning him about what he was doing.

The purchase of the BMW and leaving the keys for him to freely take, however, was the worst offense, she said, comparing the prospect to handing the unruly teen a loaded assault rifle.

'She was sitting on a ticking time bomb,' Vanker told the paper, eight months after her son's death.