A man who, as a teenager, pleaded guilty to the brutal stabbing of two married Dartmouth College professors is now challenging his life without parole sentence under New Hampshire’s Constitution.
Robert Tulloch, who was 17 at the time of the 2001 killings, stabbed Half Zantop and Susanne Zantop in their Hanover, New Hampshire, home. The killings were part of a plan hatched by Tulloch and his accomplice, James Parker, to rob and murder homeowners to finance their escape to Australia.
The duo’s plan, which involved posing as environmental surveyors to gain access to homes before robbing and killing the occupants, ultimately led them to the Zantop home. Half Zantop, 62, was a Dartmouth Earth Sciences professor, and his wife, Susanne, 55, chaired the German Studies department. Both were stabbed to death in the attack.
On Wednesday, Tulloch, now 41, is seeking a new sentencing hearing, citing protections under the New Hampshire Constitution against cruel and unusual punishment.
A hearing was scheduled Wednesday in Grafton County Superior Court to consider legal issues raised in Tulloch’s case.
The legal challenge comes in the wake of a 2012 U.S. Supreme Court ruling that found mandatory life sentences without parole for juveniles amounts to “cruel and unusual punishment.” The court’s decision later applied retroactively, opened the door for hundreds of juvenile offenders like Tulloch to seek new sentences. The Supreme Court also ruled in 2021 that judges are not required to find a minor incapable of rehabilitation to impose a life-without-parole sentence.
Newsweek reached out to the Grafton County Attorney’s office via online form for comment.

Robert Tulloch, 17, arrives in court in Lebanon, New Hampshire, on February 21, 2001. Tulloch pleaded guilty to the stabbing of two married Dartmouth College professors.
Jim Cole/AP
At least 28 states have banned such sentences for crimes committed when the defendant is a child. However, efforts to pass similar legislation in New Hampshire have not succeeded.
Under the New Hampshire Constitution, no court of law “shall deem excessive bail or sureties, impose excessive fines, or inflict cruel or unusual punishments.”
Tulloch’s lawyer, Richard Guerriero, argues that the language in the state’s constitution offers greater protection than the U.S. Constitution and that it would include sentencing someone to life without parole when they commit a crime as a child, he wrote in a memorandum.
In response, prosecutors have dismissed these claims in court documents, stating that Guerriero’s argument is not compelling and that they may seek a similar life-without-parole sentence for Tulloch.
The case has attracted support from civil liberties groups, including the American Civil Liberties Union of New Hampshire, which filed a brief in Tulloch’s favor.
Tulloch is the last of five men who awaits resentencing under a state Supreme Court ruling. Three were resentenced to lengthy terms with a chance at parole, and one was resentenced to life without parole.
James Parker, Tulloch’s former friend and coconspirator, was released on parole in 2021. Parker was 16 at the time of the murders and had pleaded guilty to second-degree murder. His testimony against Tulloch played a crucial role in securing Tulloch’s conviction. Parker served the nearly minimum sentence of his 25-year term.
This article includes reporting from the Associated Press.




