The Murder of Mary K. Ross in Sioux Falls

I'm not sure why this particular crime is one I'll never forget. I guess it has something to do with thinking that Sioux Falls, South Dakota was immune to this sort of thing.

I mean contract killings and murder-for-hire plots are something you only see in movies or on ABC's 20/20 or NBC's Dateline. Those stories that Keith Morrison narrates in that scary voice of his just draws you in.

To the best of my knowledge, no one has dramatized this murder, but if there is a movie about this, I would like to see it.

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Who was the victim and why was she murdered?

Mary K. Ross was a young mother living in Sioux Falls. Her friend Amy Power was having problems in her marriage, so Mary invited her and her child to live with her in her apartment for a while.

Ross gave Amy Power a key, which she later lost or misplaced.

This angered Amy's husband Robert Power who claimed that Mary Ross was interfering in his marriage and allegedly had smoked marijuana in front of his child.

Power offered Michael Lee Smith $10,000 or two pounds of methamphetamine to murder Ross. Smith declined but introduced him to two guys who would.

Eric Coon and Robert Poppen were each supposed to get $10,000 to murder Ross.

They believed their acts would make people fear them and provide a boost to their egos.  Poppen claimed that for he and Coon, it was all about “power and money.”  In the end, they received no more than the $50 given them to purchase the knives and gloves, though they were convinced Power would pay them as he “seemed like a nice enough person” when they contracted with him to kill Ross- -Justia U.S. Law

What happened?

Power wanted the murder done on a weekend when his wife was out of town. He gave Coon and Poppen a key to Mary's apartment, a map of her apartment and the parking lot, money to buy supplies with, and his car to get there.

Coon and Poppen went to a Hy-Vee and purchased knives, gloves, and a frying pan for Poppen's girlfriend, so it wouldn't look weird for them to just be buying knives.

When did the crime occur?

Mary K. Ross was murdered in her apartment around  4:00 AM  on July 9, 1995, while her daughter was awake in her crib in the adjacent bedroom.

The details of the crime are particularly grisly:

Coon and Poppen found Ross sleeping in her bedroom and delivered a total of 16 stab and sharp force wounds to her head and upper body.  The crime scene was particularly gruesome because Ross had managed, during the attack, to escape to the kitchen and attempt telephone contact with a 911 operator.  Coon and Poppen, whose knives broke with the force of their stabbings, rifled through kitchen drawers for knives to complete their mission.  They left Ross on her living room couch, with her throat cut, believing she was dead.- -Justia U.S. Law

Sherry Smith, Mary Ross's mother later filed a lawsuit against the apartment owners claiming that her daughter had requested that the lock on her door be changed after the spare key disappeared.

She had spoken to her daughter 3 days prior to the murder and detected fear in her daughter's voice as she refused to talk about the Power's marriage issues. She told her mom-

I do not want to talk about him; he's a psycho!- More Law

 

Robert Power was apprehended, and he pleaded guilty to first-degree murder. He was sentenced to life without parole in the state penitentiary.

Coon, and Poppen plead guilty to avoid the death penalty. Smith refused to plead guilty at first

Coon and Poppen later appealed their convictions all the way to the State Supreme court and lost.

All are serving life in prison.

Sources: South Dakota Unified Judicial System, Justia U.S. Law, and More Law.