Postal Mortem

Mark Hofmann bombing murder of Steve Christensen

Image credit: Episode screen capture from Forensic Files

A serial bomber killed two different people in the same morning. The next day, a third victim was severely injured. But this third target warranted a closer look.

Original air date: December 11, 1997

Posted: July 2, 2022
By: Robert S.

Season 2, Episode 11

Watch this episode

Early in the morning on October 15, 1985, a homemade bomb exploded on the sixth floor in an office building. Holding the package in which the bomb was concealed, 31-year-old Steve Christensen was killed instantly. The financial consultant had recently resigned his position at CFS, a real estate investment firm in Salt Lake City. The company had recently fallen under scrutiny for a series of bad investments, and their clients were enraged. Several began claiming fraud, so it seemed possible Christensen had been targeted as retaliation by a disgruntled investor.

Steve Christensen's office was on the sixth floor of the historic Judge Building in Salt Lake City
Image credit: Episode screen capture from Forensic Files

This theory gained additional support just two hours later when another bomb exploded, just outside the home of one of Christensen's former business associates. However, instead of killing the intended target Gary Sheets, the explosive had been triggered by his wife Kathleen. She'd seen a mysterious package in their driveway, picked it up for an examination, and merely tilting the device, it detonated. In a single morning, a serial bomber had murdered two former business associates. As they investigated the crime scenes, police were concerned about more potential targets.

The next day, their fears were affirmed. In downtown Salt Lake, a third victim got caught in the explosion of another pipe bomb. But this time, the target survived the blast with injuries that were not life-threatening. 30-year-old Mark Hofmann was a rare documents dealer, and had no association with the CFS investment firm. However, Hofmann did have a prior relationship with the first victim, Steve Christensen. Both were interested in historic documents from Mormon antiquity, Christensen as a collector and Hofmann as a dealer.

Evidence at all three bombing sites showed clear indications that a single culprit was behind these attacks. But Hofmann's account of events wasn't consistent with the physical evidence. He claimed he'd found a strange package in the seat of his car, it fell to the car's floorboard, and then it exploded. However, a hole in the car's door, damage to the center console, and the ruin of Hofmann's right knee told a different story. Detectives thought it strange that a bombing victim would lie about the circumstances of the incident, so this surviving victim was given a polygraph test. The lie detector indicated no deception by Hofmann.

But something still wasn't sitting right with investigators. On the morning of Steve Christensen's death, he had been scheduled to attend a meeting with Mormon officials regarding the legitimacy of a collection of documents Hofmann had intended to sell. Mark Hofmann seemed to possess an uncanny ability to locate and collect hundreds of historic records from Mormon history. Even though valuable items sold by Hofmann in the past had been authenticated, police wanted to conduct their own examination. Had Mark Hofmann meant to silence Steve Christensen, and then murdered Gary Sheets to subvert investigators' suspicions?

The Facts

Case Type: Crime

Crimes

  • Theft by deception
  • Murder
  • Fraud

Date & Location

  • October 15, 1985 through October 16, 1985
  • Salt Lake City, Utah

Victims

  • Steve Christensen (Age: 31)
  • Kathy Sheets (Age: 50)

Perpetrator

  • Mark Hofmann (Age: 30)

Weapon

  • Bomb

Watch Forensic Files: Season 2, Episode 11
Postal Mortem

The Evidence

Forensic Evidence

  • Bomb fragments
  • Document examination
  • Matching item: Gunpowder
  • Purchase record/receipt
  • Reconstruction: Accident

Forensic Tools/Techniques

  • Profile projector

Usual Suspects

No Evil Geniuses Here
?

  • Accidentally detonated own bomb

Cringeworthy Crime Jargon
?

  • None uttered in this episode

File This Under...
?

  • Graphic content
  • Karma is a bitch
  • Lie detector incorrect

The Experts

Forensic Experts

  • Jerry Taylor: ATF Explosives Expert

Quotable Quotes

A profile projector was used to identify the gunpowder granule in Hofmann's car as Hercules Bullseye brand
Image credit: Episode screen capture from Forensic Files
  • "It was real devastating to have your mother killed on your front doorstep. You feel that you’re safe in your home, and that it’s okay, and to have something like that happen really shattered your faith that things are okay." - Gretchen Sheets-Udy: Kathy Sheets’ Daughter
  • "Mark Hofmann said that he pulled open the door and the package fell from the seat of the car onto the floorboard of the car, at which time it exploded, and he was injured." - Gerry D’Elia: Prosecutor
  • "Didn’t line up with the exploding bomb. We can’t change that because the hole’s in the vehicle. That’s a true. It’s now taking the injured pieces of the individual; putting them so they come in contact with the bomb." - Jerry A. Taylor: ATF Explosives Expert
  • "We had no idea why Mark Hofmann, if he were the perpetrator, would kill a close associate and friend of his, Steve Christensen. And for all we knew, he didn’t even know Kathleen Sheets." - Robert Stott: Deputy District Attorney
  • "We had him take a polygraph, and he passed with flying colors. Not even close – he passed with a high number saying that he was not deceptive, and that he did not do the bombings." - Ken Farnsworth: Investigator
  • "Every single document that I looked at had been forged or manipulated in some way to make it valuable. And I looked at over 600 of his documents. Every single one of ‘em was forged – he never found a single, genuine document ever." - George Throckmorton: Forensic Document Examiner

TV Shows About This Case

  • Murder Among the Mormons: 2021 (3-part series)
  • City Confidential: Faith and Foul Play in Salt Lake City (s01e03)
  • Who the (Bleep) Did I Marry: An Explosive Love (s01e07)

Book About This Case

Last Words

Mark Hofmann had bought many of his bomb-making components at Radio Shack and provided the fake name 'Mike Hanson'
Image credit: Episode screen capture from Forensic Files

I've been a big nerd ever since I can remember. Obviously, I have a love for computers and web technologies, but I've dabbled in everything from music and filmmaking to pyrotechnics and electronics. From a very young age, when home computers were first being made available at reasonable prices, Radio Shack was one of my favorite stores. Just a bike ride from home and next to a huge five-and-dime store, I spent countless hours at Radio Shack. With big dreams but little money, I'd consider what I'd do if I had this computer, or what I could learn if I had that software. And toward the back of the store, they had hundreds upon hundreds of small electronic gizmos and doodads. While I didn't understand most of them, I was fascinated by the switches, integrated circuits, and other breadboard components. I even learned to interpret the color-coded banding on resistors, information I still have no use for today.

It was sad to see the decline and eventual downfall of Radio Shack. But, like Circuit City, many good (or nostalgic) things often come to an end. Mark Hofmann had purchased several of his bomb-making components from Radio Shack. From the few purchases I remember making there, I recall finding it odd that the store would ask for so much personal information. Even paying with cash, clerks were required to capture your name, phone number and even address. This practice wouldn't win friends in today's privacy-sensitive world, and it'd probably be used for marketing purposes. But Radio Shack's intentions were different – it seems they were pursuing accountability. I can see this now, as an adult. But Mark Hofmann easily thwarted their strategy when he gave Radio Shack fictitious information.

Serial bombers Mark Hofmann and James Genrich used mercury switches to trigger their homemade bombs
Image credit: Episode screen capture from Forensic Files

In Colorado, James Genrich constructed bombs with similar triggering devices just six years later, in 1991. It seems both he and Hofmann used mercury switches, a motion-sensitive trigger that completes an electrical connection when the conductive, liquid metal bridges the contacts. While you can still buy glass mercury switches, these are an older alternative to a simple tilt switch that uses a metal ball. I imagine over 30 years ago, mercury switches weren't cheap, but Amazon has comparable tilt switches for less than 10 cents apiece.

Mark Hofmann's world of deception

Mark Hofmann's deceit of seemingly everyone he came in contact with was no small achievement. You have to almost live in a fantasy world when your life is more lies than truths. I'd venture to suggest Hofmann probably even came to believe some of his own lies – to me, this explains how this perpetrator easily passed the polygraph test. Remember George Costanza's advice? "It's not a lie, if you believe it."

I had a lot of questions about how Hofmann was able to fool so many people with his "The Oath of a Freeman" original document scam. Apparently, his narrative was, "A print of this rarest of Mormon documents from the 17th century just happened to be available in a used bookstore." We're to believe he's about the luckiest collector/dealer alive to stumble on this $1m document. When Mark Hofmann thought to swindle, he thought big. Most forgers probably wouldn't dare to pass a counterfeit of one of the most famous Mormon documents in history. Risk reduction would have most imitators select items that would likely fall under less scrutiny. But Hofmann must've thought, "Go big or go home!"

Mark Hofmann told the printing company in Utah that his "The Oath of a Freeman" plate was to be used to make facsimiles
Image credit: Episode screen capture from Forensic Files

To have his fake "Oath" certified by the Library of Congress and by the FBI was quite a feat. Of course, if Hofmann's forgery was identified in the process, he could simply claim that he'd been fooled too. Even a respected rare documents dealer might have a hard time detecting a clever counterfeit. And investigators wouldn't have any reason to suspect Hofmann himself had been the perpetrator. But when a warrant gave detectives license to search his home, Mark Hofmann had not covered his tracks. A book with a recipe for iron gallotannic ink was somewhat damning. But a receipt for a printing plate for the actual "Oath" itself was impossible to refute. Ideally, one wouldn't suggest the platemaker to write "The Oath of a Freeman" on the actual receipt, but the least Mark could've done was thrown it away.

Mark Hofmann: Forger to murderer

Serial bombers like Mark Hofmann and James Genrich have to transport their bombs without detonating them. Sometimes this is by foot, sometimes by car, and sometimes both. I can imagine Hofmann's anxiety having to drive his bomb to the Judge Building, take it up in the elevator with other passengers, and set it down outside Steve Christensen's office all without triggering it. I get nervous when I bring a cake to work. And Hofmann had also done this just the night before, when he transported his other bomb to the Sheets' home.

The bomb's fragments gathered at the Steve Christensen murder scene were pieced back together to reconstruct the device
Image credit: Episode screen capture from Forensic Files

But his luck ran out on October 16th when he became one of his own victims. He'd successfully transported two other bombs, so I wonder what went wrong this time. Did he mishandle it? Was there a dangerous flaw in its construction? Whatever the reason, it probably saved another innocent person's life. But whose? Who was Mark Hofmann attempting to deliver the third bomb to in downtown Salt Lake City that day?

Steve Christensen was targeted and murdered on the very day he and Hofmann were to meet with Mormon officials regarding the McLellin collection. Did this meeting continue without Christensen, or was it postponed? And did Mark Hofmann consider the timing of Christensen's mysterious murdered on the day of the meeting would likely make him a prime suspect? Even if investigators didn't suspect Hofmann's forgeries, it's too coincidental to not at least be considered.

The episode didn't describe the construction of the bomb that killed Kathy Sheets having additional shrapnel attached, but over 100 masonry nails were part of the bomb that killed Steve Christensen. Of course, Christensen was the prime target, and Hofmann needed him dead rather than injured. It also seems the bomb that injured Hofmann was not adorned with nails, so supposedly its target wasn't as critical. Perhaps it was another former CFS employee to further throw investigators off the trail.

The heartlessness it takes to kill someone who you fear is going to expose your frauds to the public is stunning. But to then target someone entirely unrelated to your mischief, just to impede the investigation, is evil. And Mark Hofmann knew that he might end up killing someone else in either of his blasts. At Steve Christensen's office, any number of associates might have been near Steve when the bomb exploded (I later read that a secretary had been injured, taking shrapnel to the leg). And of course, at the Sheets' residence, Kathy Sheets had not been the intended target. Mark Hofmann later told the Utah Board of Pardons that he recognized the potential to injure or kill unrelated victims, and that he simply didn't care. There's a special place in hell for someone so callous.

The cracking or "alligatoring" in the ink used help experts identify Mark Hofmann's forgeries
Image credit: Episode screen capture from Forensic Files

In all, George Throckmorton examined over 600 documents that had passed through Mark Hofmann's hands. Every one of them had been forged, or at least manipulated in ways to increase their value. This shows a specific lack of restraint from Hofmann. It's likely he traded some genuine Mormon documents in his business dealings. But even these which were not forgeries were altered – it's like Mark Hofmann couldn't help himself.

Mormon murders, popularized by Netflix

In 2021, Netflix released the three-part documentary Murder Among the Mormons. I think this "long-form" true crime has been popularized with streaming services. I knew The Jinx (2015) was multiple episodes, and the series ran about 4.5 hours. It was well produced and interesting, but I felt it dragged. (And to be honest, I wasn't surprised by the ending – I'd thought the same thing about the envelope's handwriting.) And then in 2018, Making a Murderer was all the rage. After 60+ minutes, I remember thinking, "This was pretty good." It was then I realized their story had another 9 hours to go. I'm a true crime fan, but that's a bit much for me.

Murder Among the Mormons features many of the same players from the Forensic Files episode (Robert Stott, Gerry D'Elia, George Thorckmorton). So, if you're into long-form, check it out – it's not even three hours long. Its directors include Jared Hess (Napoleon Dynamite), so that can't be a bad thing. But having a series this long about bombing murders, and not featuring ATF Explosives Expert Jerry Taylor seems like a crime.

As in the episode Small Town Terror (s11e34), Jerry Taylor is an outstanding interview in the Hofmann case. Forensic Files sometimes uses a memorable one-liner as an episode's closing. This episode's might've been the best of all:

  • Narrator (Peter Thomas): "And how common is it for a bomber to blow himself up when handling one of his own bombs?"
  • Jerry Taylor: "Not common enough."

Where is Mark Hofmann now in 2024?

Mark Hofmann was arrested in early 1986 for the murders and for fraud. Legal wranglings took place for a year before Hofmann finally agreed to a plea bargain in January 1987. Mark Hofmann pleaded guilty to two counts of second-degree murder, fraud, and theft by deception. His sentence was "five years to life" based on Utah's sentencing guidelines at the time, but the judge recommended that Hofmann remain incarcerated for the remainder of his natural life. In 1988, the Utah Board of Pardons agreed with the judge that Hofmann should never be released from prison. Mark Hofmann is currently incarcerated at Central Utah Correctional Facility in Gunnison, Utah.

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Author Robert S. profile image
Robert S.
I've been a fan of Forensic Files since the show's inception, and it is still my favorite true crime series. I have seen every episode several times, and I am considered an expert on the series and the cases it covers.