Mary Agnes Leider

Case record: Mary Agnes Leider

Background

Mary Agnes Leider was 25 years old, from Saint Xavier, on the Crow Indian Reservation. She was an enrolled member of the Crow Tribe of Indians. She threw her 3-year-old daughter out of a moving pickup truck.

The victim was Tenielle Ameryl Big Day, aged 3. Tenielle died in the December 2012 death involving the moving pickup truck. Her grandparents, Heywood and Veronica Big Day, were described as the primary caregivers for the 3-year-old girl.

Tennison Big Day was Tenielle's father. Heywood Big Day III was Tenielle's uncle. Tennison Big Day and Heywood Big Day III gave statements during the sentencing.

Mary Leider also had a daughter who died in December of 2009, which Judge Donald Molloy noted during sentencing, and he questioned whether it was possible for Leider to be a good mother.

The offence

Authorities investigated Tenielle Big Day’s death as a homicide. Tenielle died when Leider threw her out of a moving pickup traveling at highway speeds.

Leider’s brother W.L. reported that Leider was seated in the front passenger’s seat with the victim on her lap. W.L. reported that while they were driving south towards St. Xavier, Leider opened the front passenger door with her right hand and threw the victim out of the moving pickup.

Court documents and investigators described the truck’s speed at the time the victim was thrown as between 45 and 51 miles per hour, and one account said the vehicle was going at least 45 mph and was going 50 miles per hour.

During the hours leading up to Tenielle’s death, Leider and two brothers had been drinking, including drinking a quart of gin and up to 60 beers. Leider’s blood alcohol level was reported as more than 0.24 percent, which was described as three times the legal limit for driving.

In the sentencing proceedings, Assistant U.S. Attorney Lori Suek described the crime as "unimaginable." Judge Donald Molloy called it "incomprehensible" and questioned how a mother could kill her own child.

Investigation

FBI agents sought a warrant to search a pickup truck registered to Mary Agnes Leider. The truck was described as a purple 1999 Dodge pickup. The pickup was at Big Horn County’s impound yard in Hardin.

The search sought hair, fibers, bodily fluids containing DNA, and any item related to the pickup’s operation. In the search warrant application, the FBI described what it suspected happened based on interviews with witnesses.

According to witness statements described in the court materials, Wally Leider told investigators that Mary Leider had thrown her daughter out of the pickup while he was driving. Wally Leider said the girl was “quiet but awake” when Mary Leider opened the front passenger door and threw Tenielle out of the pickup. Wally Leider immediately stopped and Mary Leider got out of the pickup. He found Tenielle and knew she was dead, then picked up the child, put her in the back seat, and drove toward his mother’s house.

Mary Leider told officers she was driving around with her daughter and drinking with her brothers when her brothers began arguing on the way home. She said she told Wally Leider to slow down, and that she hit her head on the dashboard at some point. She gave statements that she could not remember what had happened to the child when the pickup stopped or how her daughter got injured.

The case involved 911 calls that were tracked to an area near mile marker 11 on Highway 313 south of Hardin. Dispatch and responders responded to calls identified as coming from that area at approximately 4:06 a.m. on December 3. Law enforcement found Leider and her brother, Arland Leider, sitting to the side of the road and crying uncontrollably. Leider told law enforcement that her baby was “gone” and had been hit by a vehicle.

A second 911 call resulted in additional law enforcement responding to mile marker 19 on Highway 313. At the second location, Wally Leider and Georgiana Denny were present. Georgiana Denny was described as the mother of Mary, Wally, and Arland Leider. Denny showed the deputy Tenielle’s lifeless body, and Tenielle’s body was in Denny’s car when the deputy arrived.

G.D. later advised that her daughter (Leider), along with her two sons, had been out partying during the evening of December 2, 2012, and had taken the victim with them. G.D. reported that she repeatedly called and text messaged her children to have Leider come home with the victim, but Leider refused. G.D. reported that she left to find Leider and the victim while traveling north on Highway 313, and that both vehicles stopped. G.D. saw Leider’s pickup being driven by W.L. W.L. told G.D. that something was wrong with the victim. G.D. saw that the victim was not breathing and not responsive. W.L. told G.D. that Leider had thrown the victim from the pickup. When G.D. picked up the victim, she saw blood coming from the back of her head. She called an ambulance and put the victim in her car.

Following the arrival of law enforcement at the scene, Leider was taken to Hardin Memorial Hospital to have her blood drawn and for treatment for abrasions to her face. While at the hospital, she alternated between claiming that her daughter died in a car accident and saying, "I killed my baby." When questioned by law enforcement, she admitted that she had been driving around and drinking with her brothers but claimed that she hit her face on the dashboard and could not recall how the victim was killed.

Investigators determined that the vehicle had not been in an accident, and an autopsy was conducted. Following the autopsy, the victim’s probable cause of death was determined to be severe head injuries caused when thrown from a moving motor vehicle.

The investigation involved a cooperative effort between the Bureau of Indian Affairs and the Federal Bureau of Investigation.

Arrest and detention

Leider remained in custody while awaiting sentencing.

Later on the scene timeline described in one account, Mary Leider was booked into the Yellowstone County jail on a warrant from Billings Municipal Court for revocation of a suspended sentence for traffic violations. She was released on Dec. 9.

On February 26, 2013, at a brief arraignment before U.S. Magistrate Judge Carolyn Ostby, Leider pleaded not guilty to second-degree murder.

On February 8, 2013, a federal criminal complaint for second-degree murder was filed against Mary Leider. She made her first court appearance on the second-degree murder complaint, waived a preliminary hearing, and a detention hearing had not been scheduled.

Trial and plea

Leider pleaded guilty in July. In the July 24, 2013 federal court proceedings, she pled guilty to second-degree murder.

The July 24, 2013 proceedings reported that during a federal court session in Billings on July 24, 2013, before U.S. District Judge Donald W. Molloy, Mary Agnes Leider, a 25-year-old resident of Crow Agency, and an enrolled member of the Crow Tribe of Indians, pled guilty to second-degree murder. Sentencing had been set for October 22, 2013, and she was detained.

In an Offer of Proof filed by Assistant U.S. Attorneys Jessica T. Fehr and Lori Harper Suek, the government stated it would have proved at trial that:

• On December 3, 2012, at approximately 4:06 a.m., 911 operators from the Big Horn County Sheriff’s Office began receiving phone calls identified as coming from the area of mile marker 11 on Highway 313 south of Hardin.
• Operators dispatched law enforcement and an ambulance.
• When law enforcement arrived, Leider and her brother, A.L., were found sitting to the side of the road crying uncontrollably.
• Leider told law enforcement her baby was “gone” and had been hit by a vehicle.
• A later 911 call dispatched additional law enforcement to mile marker 19, Highway 313.
• Upon arrival, law enforcement were met by G.D. and her son, W.L. G.D. took an officer to her car, where a 3-year-old female was found.
• The child appeared to already be deceased and was identified as Leider’s daughter.
• G.D. told law enforcement that Leider and her two sons had been out partying during the evening of December 2, 2012, and had taken the victim with them; G.D. repeatedly called and text messaged her children, but Leider refused to come home.
• Early on December 3, 2012, G.D. left to find Leider and the victim, traveling towards Hardin, and saw Leider’s pickup being driven by W.L.
• G.D. saw that Leider’s pickup had the victim in the backseat; W.L. told G.D. something was wrong with the victim, that the victim was not breathing and not responsive, and that Leider had thrown the victim from the pickup.
• G.D. observed blood coming from the back of the victim’s head, called an ambulance, and put the victim in her car.
• W.L. stated he was driving Leider’s pickup early in the morning on December 3, 2012, with Leider in the front passenger’s seat and the victim on her lap.
• W.L. reported that at the time the victim was quiet but awake; Leider opened the front passenger door with her right hand and threw the victim out of the moving pickup.
• W.L. and the reconstructionist from the Montana Highway Patrol estimated the truck was traveling between 45 and 51 miles per hour.
• W.L. stopped as fast as he could, threw Leider out of the truck with A.L., then went back down the road behind the truck to where the victim was lying in the roadway, knew she was dead, carried her back to the truck, placed her in the backseat, and drove towards home, leaving Leider and A.L. by mile marker 11 where they were found by law enforcement.
• Following law enforcement arrival, Leider was taken to Hardin Memorial Hospital for blood draw and treatment for abrasions.
• Leider’s blood alcohol level was found to be over a 0.24 when analyzed by the FBI Laboratory.
• While there, she alternated between "I killed my baby" and claiming the group had a car accident and that was how the victim had died.
• Investigators also stated that Leider’s pickup was impounded and towed for analysis; the right front passenger door was analyzed and was found to function properly.
• The probable cause of death was determined to be severe head injuries caused when thrown from a moving motor vehicle.

The July 24, 2013 proceedings also stated possible penalties included life in prison, a $250,000 fine, and five years’ supervised release.

Sentencing

On October 23, 2013, Judge Donald Molloy sentenced Mary Agnes Leider to 262 months in prison, described as just under 22 years, with no chance of parole. In one account this was described as 21 years and 10 months. The sentence was for second-degree murder.

The sentencing included statements by Leider, the victim’s uncle, and the victim’s father.

• A federal public defender, David Merchant, said Leider had experienced stress, guilt, and shame and requested that her sentence be set at 15 years to allow her more time to get her life in order after she is released.
• Leider made a tearful statement apologizing for causing family members to suffer:

  "Nothing can bring her back and I have to live with that."

• Assistant U.S. Attorney Lori Suek described the crime as "unimaginable." She pushed for the maximum sentence of 262 months.
• Heywood Big Day III gave an emotional statement speaking on behalf of family members. He described the role of Tenielle’s grandparents, Heywood and Veronica Big Day, as primary caregivers and said they now felt guilt because they believed they should not have let Tenielle go:

  "We cry ourselves to sleep because there is nowhere else to go,"

• Tennison Big Day also expressed sadness and frustration in statements during the sentencing.

Judge Donald Molloy stated that the family's statements and his review of the case made it hard for him to understand how a mother could kill her own child. He also said he had been shocked by the amount of violent crime and alcohol abuse on the reservation since he began his temporary role as a federal judge in Billings and that there was a need for someone within the Crow Tribe to step forward and tackle crime and substance abuse on the reservation.

Judge Donald Molloy also characterized the case and his reactions in another account: he wanted to keep the 25-year-old defendant from doing further harm and send a message about the dangers of alcohol abuse on the reservation. He said that in 18 years on the bench he had never encountered such depravity in a criminal case and that the details made him nauseous:

"How could a mother do this to her own child?" He also said tribal members needed to stand up and say "enough is enough. Stop the drinking and the drugs and the violence."

Leider was ordered to pay $11,123 restitution to cover Tennielle’s funeral costs and her father’s lost wages.

Appeals

No appeals were included in the provided material.

Outcome

Mary Agnes Leider received a prison sentence of 262 months with no chance of parole.

Aftermath

During sentencing in federal court, relatives packed the courtroom. Heywood Big Day III described the death reverberating through the Crow reservation, where children play a central role as the future of the tribe. He described that Tenielle’s grandparents blamed themselves for not keeping the girl away from Leider, who had previous drunken driving offenses and a longstanding problem with alcoholism.

A family member described Tenielle as a Lego-loving baby who liked to perform traditional Crow dances and was raised primarily by her grandparents.

An obituary published in the Billings Gazette described Tenielle Big Day as:

"an active child who loved to play outdoors with her friends. She often enjoyed building castles with her Lego blocks. She loved to dance and was a traditional Crow dancer."

Other details

On February 26, 2013, second-degree murder was described as knowingly killing a person with malice aforethought and carrying a maximum penalty of life in prison and a possible $250,000 fine.

On February 26, 2013, Leider appeared in court earlier that month on a criminal complaint filed in the case and pleaded not guilty at the arraignment before U.S. Magistrate Judge Carolyn Ostby. Ostby continued Leider’s detention, and the case was to be heard by Chief U.S. District Judge Richard Cebull.

In one account, the courtroom described by a judge recounted Tenielle’s injuries and stated: "Head and brain were smashed and spinal cord destroyed ... by the stupidity of her mother."