Dennis Sweeney was a former Mississippi civil rights volunteer who, on March 14, 1980, shot and killed his onetime mentor, former U.S. Congressman Allard K. Lowenstein, in Lowenstein’s Rockefeller Center law office in Manhattan. Sweeney had developed paranoid schizophrenia, and his delusions had fixed on Lowenstein for years before the killing. A New York court found him not responsible by reason of insanity in 1981 and committed him to the state mental health system, where he remained under some form of supervision for roughly two decades before being released from psychiatric oversight around 2000.
How Sweeney and Lowenstein Met
The two met at Stanford University in the early 1960s, where Lowenstein briefly served as a dean. Lowenstein, a Yale-trained lawyer who would go on to serve one term in the U.S. House from New York between 1969 and 1971, was known above all for pulling young people into political work.1U.S. House of Representatives History, Art & Archives. Allard Kenneth Lowenstein Journalist David Broder wrote that “it is beyond dispute that he brought more young people into American politics than any individual of our time.”2Yale Law School. Biography of Allard K. Lowenstein
Sweeney was one of those recruits. In his 1982 book Dreams Die Hard, David Harris, a Stanford contemporary, described how Lowenstein drew young men who revered him, took them along on what Harris called “errands for change,” and could throw them “into some political breach.”3The New York Times. A Protégé’s Story In 1964, Lowenstein was recruiting white college students from Yale and Stanford for Mississippi’s Freedom Summer voter registration drives.1U.S. House of Representatives History, Art & Archives. Allard Kenneth Lowenstein Sweeney went.
Mississippi and the Onset of Illness
Sweeney was stationed at the McComb Freedom House in McComb, Mississippi, one of the most dangerous postings for civil rights workers. At about 3:50 a.m. on July 8, 1964, the house was bombed. Sweeney, one of ten residents present, sustained minor cuts and a mild concussion. In a sworn affidavit he noted that local police dismissed the explosion as having been caused by “termites” and that it remained unsolved alongside twelve other bombings in the area.4Civil Rights Movement Archive. SNCC McComb Sweeney Affidavit Harris later described the bombing as leaving Sweeney with “badly concussed eardrums.”5David Harris. Dreams Die Hard – Excerpt From Chapter 4
In the years that followed, his mental health deteriorated. He was eventually diagnosed with paranoid schizophrenia. According to New York Times reporting, Sweeney began hearing voices more than twenty years before the killing, placing the onset in the late 1950s or early 1960s.6The New York Times. Plan to Release Notorious Killer Prompts Debate About Insanity The delusions increasingly centered on Lowenstein. After his arrest, Sweeney told psychiatrists he believed Lowenstein was part of a “Jewish plot to destroy him” and attributed those convictions to voices in his head.7The New York Times. Voices in His Head Muted, Killer Rejoins World One account described his belief that Lowenstein had implanted a transmitter in his teeth that was sending him messages.8Physicians for a National Health Program. A Predictable Tragedy in Arizona
Duke historian William Chafe, whose 1993 biography Never Stop Running drew on Lowenstein’s papers and about 150 interviews, wrote that Sweeney had “turned psychotic” and become “obsessed with Lowenstein,” holding his former mentor responsible for his personal misery and tracing his unhappiness back to their time in the Mississippi movement.9The Washington Post. A Pied Piper of the ’60s
The Shooting at Rockefeller Center
On the afternoon of March 14, 1980, Sweeney, then 37, walked into Lowenstein’s law office at Rockefeller Center and shot him five times in the chest.3The New York Times. A Protégé’s Story Lowenstein, 51, was taken to St. Clare’s Hospital on West 51st Street, where surgeons operated for five and a half hours. His heart stopped five times during the surgery and was restarted each time. About thirty minutes after the operation ended, it stopped a sixth time and did not respond to further treatment. He was pronounced dead roughly seven hours after being shot.10The New York Times. Efforts to Save Lowenstein Typify Emergency Service Lowenstein was later interred at Arlington National Cemetery.1U.S. House of Representatives History, Art & Archives. Allard Kenneth Lowenstein
Not Responsible by Reason of Insanity
Sweeney was charged with murder in New York State Supreme Court. He pleaded not responsible by reason of insanity, and the state did not dispute the plea.6The New York Times. Plan to Release Notorious Killer Prompts Debate About Insanity Under New York Penal Law § 40.15, a defendant is not criminally responsible if, at the time of the act, a mental disease or defect caused them to lack the substantial capacity to know or appreciate either the nature and consequences of their conduct or that it was wrong.11New York Courts. CJI2d – Insanity Defense
On February 23, 1981, an acting state Supreme Court justice found Sweeney not responsible by reason of insanity.12The Washington Post. Ex-Rep. Lowenstein Killer Adjudged Not Responsible for Reasons of Insanity Instead of a prison sentence, he was committed to the custody of the New York State mental health system.
What Happened to Sweeney After the Verdict
Sweeney was sent to a state mental hospital in Middletown, New York, about 70 miles northwest of Manhattan.7The New York Times. Voices in His Head Muted, Killer Rejoins World Over nearly two decades, his restrictions were gradually loosened. By the mid-1990s he was living in the community, required only to return to the Middletown hospital twice a month for overnight stays of about six hours: arriving around midnight, reporting to the duty nurse, sleeping in an empty bed on the third floor, and leaving at dawn.
On June 30, 2000, State Supreme Court Justice Brenda Soloff ruled that Sweeney, then 57, no longer required inpatient psychiatric hospitalization. She wrote that the question had already been “answered in the negative,” observing that “for some six years, without medication, Dennis Sweeney has been building an ever more complex, satisfying and successful life in the community.”6The New York Times. Plan to Release Notorious Killer Prompts Debate About Insanity Prosecutors and state mental health officials opposed the ruling, arguing that Sweeney still needed supervision at a psychiatric facility. By July 2000, the twice-monthly hospital requirement was discontinued, effectively ending the psychiatric and legal oversight that had begun with his 1981 commitment.7The New York Times. Voices in His Head Muted, Killer Rejoins World