Captain Frank ‘Marty’ Theer, US Air Force, was murdered on December 17, 2000 in Fayetteville, North Carolina. Military and civilian prosecutors believe Marty was murdered by his wife Michelle Theer and her lover SSG John Diamond, a sniper in the US Army stationed at Fort Bragg. Michelle tried to claim that John was obsessed with her and killed Marty so he could be with her. John Diamond’s defense team claimed that Michelle killed Marty for his large life insurance policy and set John up to take the fall. Prosecutors theorized that Michelle Theer manipulated John Diamond into committing the murder by claiming that Marty abused her. John’s family believe that the Army railroaded John because he was an enlisted man accused of killing an officer. In the end they would both be convicted of the murder of Marty Theer and spend the rest of their life in prison.
“Michelle Theer was named as a conspirator by Army prosecutors, but they had no jurisdiction over her because she is a civilian. She has not been charged in civilian courts.” -FayObserver (5/19/2002)
Investigation Discovery:
In 2000, Michelle Theer was an Air Force wife in the military town of Fayetteville until a fatal shooting made her a widow. The investigation into her husband’s death led police to the door of an Army Ranger – taking orders from very unlikely accomplices. -Fayetteville, Sins and Secrets (S2,E3)
Sexy psychologist and doting Air Force wife Michelle begins a swinging affair with Army Sgt. Diamond while her husband, Captain Marty Theer, is away. But all’s fair in love and war, and Marty’s return will remind them that love is a battlefield. -Sergeant Swinger, Scorned: Love Kills (S4,E1)
Oxygen:
A frantic, distraught woman runs into a video rental store screaming that her husband has been shot. -Michelle Theer & John Diamond, Killer Couples
Killer Couples: S8 E5 Preview – Michelle Theer and John Diamond | Oxygen
Killer Couples: S8 E5 After the Verdict – Michelle Theer and John Diamond | Oxygen
Psychologist Debbie Layton-Tholl talks about her experience meeting with Michelle Theer. -Michelle Theer & John Diamond, Killer Couples
A lonely military wife and psychologist go searching for sex on the Internet with deadly results. -Michelle Theer & John Diamond, Killer Couples (S8,E5)
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Related Links:
Diamond guilty of murder
Army Sergeant Gets Life For Killing Lover’s Husband
The Wife He Left Behind
Army Court of Criminal Appeals: US v John Diamond (2001)
Supreme Court of the US: John Diamond, SSgt, US Army v USA
Free John Diamond
Air Force wife in N.C. convicted of killing officer
Makeover Madness
Wife Sought for Husband’s Slaying Alters Face
Changed face can’t shield fugitive
Wife Of Slain Soldier Charged With Murder
Air Force widow convicted of murder punished for escape
Verdict relieves victim’s mother – The Murder of USAF Captain Marty Theer
Court of Appeals: State of North Carolina v. Michelle Theer (2007)
Court Denies Appeal for Michelle Theer
Conviction of pilot’s wife in killing upheld
Technological private eye finds what computer lost
Psychologist jailed for husband’s murder in ’04 now in solitary on suspicion of plotting prison break
Possible Jail Break Busted
Murdered N.C. airman’s wife probed in prison break
Convicted killer wants prison to stop censoring his racy letters
Murder brings ‘Dateline NBC’ to Fayetteville — again
Notorious Fayetteville crimes, Theer and Shannon homicides, to be on national TV again
Investigator: Did Michelle manipulate for murder?
Psychologist Michelle Theer, Her Internet Affair with John Diamond, and The Murder of Air Force Captain Marty Theer
Book: The Officer’s Wife by Michael Fleeman (Amazon)
Book: The Officer’s Wife | Michael Fleeman Official Website
Murder Along the Cape Fear: A North Carolina Town in the Twentieth Century
The Real Gone Girl: The True Story of Michelle Theer by Darla Pugh
Dateline: “Deadly Triangle”
Fayetteville | Sins and Secrets | Investigation Discovery (S2,E3)
Fayetteville | Sins and Secrets | Investigation Discovery (website)
Fayetteville | Sins and Secrets | Investigation Discovery (Amazon)
Sergeant Swinger | Scorned: Love Kills | Investigation Discovery (S4,E1)
Sergeant Swinger | Scorned: Love Kills | Investigation Discovery (website)
Sergeant Swinger | Scorned: Love Kills | Investigation Discovery (Amazon)
Killer Couples: S8 E5 Sneak Peek – My Husband Has Been Shot! | Oxygen
Killer Couples: S8 E5 Preview – Michelle Theer and John Diamond | Oxygen
Killer Couples: S8 E5 After the Verdict – Michelle Theer and John Diamond | Oxygen
Killer Couples: S8 E5 Bonus Clip – Michelle Was Villified by the Media | Oxygen
Michelle Theer & John Diamond | Killer Couples | Oxygen (S8,E5)
Michelle Theer & John Diamond | Killer Couples | Oxygen (Amazon)
Army SSG John Diamond Convicted of Murder of Air Force Capt. Frank Theer; Military Court Sentenced to Life in Prison, No Parole (August 28, 2001)
Former Air Force Reservist Michelle Theer Convicted of Murder of Husband Frank Theer; Sentenced to Life in Prison, No Parole (December 3, 2004)
Sins and Secrets Premiered ‘Fayetteville’ on Investigation Discovery: Michelle Theer & John Diamond Left a Permanent Mark on Community (January 26, 2012)
Scorned, Love Kills Premiered ‘Sergeant Swinger’ on ID: Air Force Captain’s Murder Reveals Wife’s Evil Intent, Adultery & Greed (October 4, 2014)
Killer Couples Premiered ‘Michelle Theer & John Diamond’ on Oxygen: Affair Leads to Murder of Air Force Capt. Marty Theer (September 3, 2016)
Scorned, Love Kills: 6 Active Duty Military Homicide Cases Featured on Investigation Discovery
MILITARY JUSTICE FOR ALL 
This is showing on Oxygen Channel as I’m typing this. Michelle Theer could have divorced Marty Theer and walked away, but she chose not to, conspired with John Diamond to kill Marty, and went on the run to avoid being held accountable for committing this heinous, unnecessary murder. I’m glad law enforcement stay on the case, found her, prosecuted her, and that she was finally convicted for the role she played in her husband’s death. He kept trying to stay in the marriage by attending counseling sessions with her, but I wish he’d walked away. Staying cost him his life. I read Marty’s bio, and he seems to have been a nice guy from a loving family who just so happened to fall in love and marry the wrong person. How sad to lose one’s life at 31-years-of age.