Legal Scholar Examines Alienation of Affection Tort as Sinema Fights Marriage Lawsuit

Former U.S. Senator Kyrsten Sinema continues defending against a civil lawsuit rooted in an archaic legal doctrine that remains viable in only six states. The action, filed by Heather Ammel against the Arizona Democrat, invokes the tort of alienation of affection—a remedy that allows spouses to sue third parties for interference in their marriages. Legal scholars suggest the case may become one of Sinema’s most significant contributions to jurisprudence, testing whether such “heart balm” actions survive modern constitutional scrutiny.

Sinema has acknowledged having an extramarital relationship with Matthew Ammel, her former security guard, while serving as a senator. The pair engaged in sexual encounters across multiple states, including California, New York, Colorado, Arizona, and Washington, D.C., according to court filings and deposition testimony. Ammel was married to Heather at the time, and the couple separated on November 1, 2024, before divorcing in March 2026.

The legal question hinges partly on jurisdiction. Sinema’s legal team moved the case to federal court and sought dismissal, arguing that no sexual encounters occurred in North Carolina, where the lawsuit was filed and where alienation of affection remains actionable. The core issue examines whether the harm to the marriage itself provides sufficient nexus to North Carolina courts, regardless of where the alleged misconduct physically transpired.

Alienation of affection traces to 17th-century English common law, originally treating wives as property whose “service and affection” belonged exclusively to husbands. The landmark case Winsmore v. Greenbank (1745) established that a paramour could be held liable for “persuading, procuring and enticing” a spouse away. Most modern jurisdictions have abolished this tort on constitutional grounds, leaving only Hawaii, North Carolina, Mississippi, New Mexico, South Dakota, and Utah recognizing the action.

Critics contend the tort reflects outdated patriarchal assumptions incompatible with contemporary values around consensual relationships between adults. The Supreme Court has never ruled alienation of affection unconstitutional, distinguishing it from criminalization of private conduct. Legal experts debate whether holding third parties liable for consensual affairs differs fundamentally from prosecuting the consensual acts themselves.

The Ammel lawsuit contains substantial evidence of the affair’s depth. Text messages recovered from Ammel’s phone included Sinema writing, “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.” Heather Ammel discovered the relationship after finding such communications and subsequently urged her husband to end the affair, describing Sinema as “insidious” and “a woman who is willing to break up a family.”

An evidentiary hearing is scheduled for August 19. The case raises fundamental questions about whether states retain authority to recognize tort recovery for emotional injuries stemming from infidelity, even as criminal adultery statutes have been largely eliminated. Some legal observers suggest that attributing marital breakdown to a third party, rather than the unfaithful spouse, perpetuates problematic assumptions about individual accountability.