Douglas Herlihy, 40, of Milford, pleaded guilty, on Oct. 21, to beating his 50-year-old father, Paul, to death in the summer of 2003. Courtesy photo

CONCORD – Douglas Herlihy, 40, of Milford, pleaded guilty, on Oct. 21, to beating his 50-year-old father, Paul, to death in the summer of 2003.

According to state Attorney General John Formella’s office, the incident took place between Aug. 23-24, 2003. Herlihy was 17 years old at the time.

Herlihy was initially charged with second-degree murder, manslaughter and attempted falsification of physical evidence. However, the murder charge was dismissed as part of the plea agreement.

“This case is a reminder that the pursuit of justice does not end with the passage of time,” said Formella. “The New Hampshire Cold Case Unit and our law enforcement partners remain committed to pursuing answers and accountability, even decades after a crime. That work takes persistence, patience and a determination to follow the evidence wherever it leads. I commend the investigators and prosecutors whose continued efforts brought this case to an important resolution.”

Under the plea agreement, Herlihy faces a stand-committed sentence of up to 24 years in prison for manslaughter. His sentence could be reduced by one year if he completes the Focus program while he is incarcerated.

The charge of attempted falsification of physical evidence carries a penalty of up to seven years in prison. However, under the plea agreement, the penalty will be suspended for 20 years.

Sentencing is scheduled for early-2027.