Former Sen. Kyrsten Sinema acknowledged under oath that she carried on a months-long sexual relationship with her married security guard, and now his ex-wife is suing her under a North Carolina law that holds third parties liable for wrecking a marriage.
Sinema sat for a deposition on July 31 at a law office in Raleigh, North Carolina, and described in plain terms how the relationship with Matthew Ammel began at an Airbnb in Napa, California, around Memorial Day 2024. Ammel was still married, still employed as her bodyguard, and the father of three children. Sinema said she knew all of that at the time.
The deposition is part of a civil lawsuit filed by Ammel's ex-wife, Heather Ammel, who accuses Sinema of destroying her 14-year marriage. Heather Ammel brought the case under North Carolina's alienation-of-affection statute, one of a handful of state laws that allow a spouse to sue a third party for interfering in a marriage. She is seeking more than $25,000 in damages, according to court filings reviewed by the New York Post. A separate filing reported by the AP puts the figure at $75,000 or more.
Sinema's own testimony traces a relationship that moved from coast to coast while she was still a sitting U.S. senator representing Arizona. She described the first encounter in Napa bluntly, as Fox News Digital reported:
"We were staying at an Airbnb in Napa, California. We were outside. Matt kissed me. We went inside and had sex."
Friends of Sinema, Penny and Grant Croissant, and another member of her security detail were also staying at the property at the time.
The second encounter came in June 2024 in New York City, where Sinema attended the wedding of CNN anchor Jessica Dean. Sinema and Ammel had separate hotel rooms but were, in Sinema's word, "intimate" in her room. By mid-July 2024, Sinema testified, the two had sex again at her apartment in Washington, D.C., after she took a red-eye flight from the West Coast. A fourth encounter followed in mid-August 2024 in Aspen, Colorado, during what was described as a "fundraising trip."
A fifth encounter in late September 2024, again in Washington, was one Sinema said she could not recall. Matthew Ammel confirmed it in his own deposition. The sixth took place at Sinema's house in Phoenix in October 2024.
All six encounters occurred between Memorial Day and October 2024, roughly five months. The Ammels separated on November 1, 2024. Their divorce was finalized in March 2026.
Heather Ammel's account of discovering the affair adds a layer of detail the deposition testimony alone does not capture. She told lawyers she first became suspicious when her husband came home "severely intoxicated" while the couple was staying at her parents' house. She later found messages between Sinema and her husband on the encrypted messaging app Signal, described in court papers as "romantic and lascivious."
One of those messages, a screenshot of which appeared in court filings, was read aloud during Heather Ammel's deposition:
"I hope your day was okay. Thinking of you. I am with you. I keep waking up during my sleep and reaching over for your arms to hold me."
Sinema acknowledged writing another message to Ammel: "Putting my hand on your heart. I'll see you soon. I miss you." When a lawyer asked whether she understood that a wife reading such a message "might get concerned about who is sending her husband that kind of message," Sinema answered, "Yes."
In a June 2024 text to her husband, Heather Ammel called Sinema "insidious" and "a woman who is willing to break up a family." She also described her ex-husband as an "established liar and manipulator" and said she believed he was "actively manipulating" both her and Sinema.
Sinema's attorneys have not disputed the substance of the affair. Their defense rests on procedure. After Heather Ammel filed the case in a North Carolina state court, Sinema's legal team moved it to federal court and filed a motion to dismiss. The argument: every sexual encounter took place outside North Carolina, and the federal court therefore lacks personal jurisdiction over Sinema.
In her court motion, Sinema's side stated plainly what happened, as Breitbart reported:
"Defendant admits that she and Plaintiff's husband, Matthew Ammel, began a romantic relationship in May 2024, about five months prior to his separation from Plaintiff."
Sinema's legal team also subpoenaed Heather Ammel's therapist records. Ammel's attorney, Thomas Van Camp, objected, calling the request "completely unrelated to the issue of Defendant's contacts with North Carolina."
An evidentiary hearing in the case is scheduled for August 19, Just The News reported, citing court documents.
Matthew Ammel joined Sinema's security detail after retiring from the Army in 2022. In that role, he accompanied the senator on trips to locations including Napa Valley, Las Vegas, and Saudi Arabia. The relationship between a sitting senator and the armed guard assigned to protect her raises questions about power dynamics and professional boundaries that the lawsuit itself does not directly address, but that the facts make difficult to ignore.
Sinema, a Democrat who later became an independent, left office at the beginning of 2025 after choosing not to seek re-election. She was unmarried at the time of the deposition.
One exchange from the deposition captures the disconnect between how Sinema framed the relationship and how the evidence reads. When lawyers asked about a photograph showing cupping marks on her body, a photo apparently connected to the affair, Sinema responded: "I'm an endurance athlete. So a photograph of me with cupping marks is about sports."
Heather Ammel's lawsuit paints a different picture of the marriage before Sinema entered the frame. Her filing stated that she and Matthew Ammel had "a good and loving marriage" with "genuine love and affection" before Sinema interfered.
North Carolina is one of a small number of states that still allow alienation-of-affection lawsuits, civil claims that let a spouse sue a third party for conduct that damaged or ended a marriage. The law does not require proof that the third party acted alone in causing the breakup, only that their conduct was a contributing factor. For Sinema, the legal exposure is real, even if her attorneys believe they can knock the case out on jurisdictional grounds before the merits are ever reached.
Whether the federal court agrees that it lacks jurisdiction will likely turn on the August 19 hearing. If the motion to dismiss fails, Sinema could face a trial on whether her conduct contributed to the collapse of the Ammels' marriage, a question the deposition testimony already answers in considerable detail.
Sinema admitted the affair. She admitted she knew Ammel was married with three children. She admitted she understood how a wife would feel reading the messages she sent. The only question left is whether a court will hold her accountable for it, or whether a jurisdictional technicality will let her walk away.
