Before 51-year-old William “Billy” Sinclair became the subject of an islandwide manhunt on Kauaʻi for suspected murder and another shooting, he was a threatening presence in the quiet Kīlauea neighborhood where he lived, according to three of his neighbors who petitioned and were granted 3-year restraining orders against him.
The first temporary restraining order against Sinclair was granted to Gilbert Alapai on Aug. 29. Alapai wrote in his petition that Sinclair had entered his home on Kīlauea Road in July and “pulled a knife (bigger than a forearm)” and swung it around. Sinclair also stated for Alapai to get out of his own house.
Alapai didn’t report that incident. But he said Sinclair entered his house without permission again on Aug. 16, walked though his kitchen and living room, and pointed a gun in his face. He kept repeating “get out of my house, get on the ground.” Alapai said Sinclair then drove off on a bike. This time, he reported the incident to police, he said.
Four months later, in December 2025, Cassiah Linn and Leonel Calvan, also neighbors of Sinclair, requested a temporary restraining order against him for “ongoing harassment and threats that have created a hostile and unsafe environment” for their family, which includes elderly parents and a 13-year-old. The Fifth Circuit Court approved it in January.
The couple, which has two dogs, said in their petition that on Nov. 29 Sinclair pounded on their door, aggressively yelling and demanding to speak to the “owners of the dogs.” A visiting relative, who was at the home with her kids, answered the door was told by Sinclair: “Tell your brother to take care of his dogs or I will.”
The couple said another incident occurred the next day over their dogs barking despite Sinclair’s dog being unleashed. Again, Sinclair yelled threats, including: “Tell your dogs to shut the (expletive) up, or I’ll do it for you.”
After both incidents, the couple called police. The second time, police spoke with Sinclair after which it was recommended to the couple to seek a TRO, the petition said.
But it led to an escalation of the threats, the petition said. Sinclair returned to the couple’s property and yelled racial slurs, threatening: “I’m gonna make your life a living hell.” He also rode by their home twice with his motorcycle the same day, “revving the engine in an intimidating manner.” The couple wrote in the petition they were fearful for their family and their dogs’ lives.
Sinclair now is wanted in connection with a homicide in Hanalei. It is not known what time it occurred, but officers responded at 12:50 a.m. on Saturday. The identity of the victim has not been disclosed.
Less than four hours later, police were dispatched at about 4:45 a.m. to reports of gunshots in Kīlauea. A resident sustained minor injuries after being grazed by a bullet.
Police said Sinclair was identified as a person of interest in both cases.
The ongoing manhunt for him has heightened concerns among residents in Kīlauea, Hanalei and surrounding communities, where law enforcement officers maintained an increased presence throughout the weekend.
On Saturday, police searched for Sinclair for about 12 hours around Sinclair’s home and neighborhood on Kīlauea Road. Police closed off that road between Kolo Road and Kaikala Street and evacuated nearby residents.
The police put out alerts about the road closure, but did not communicate to the public why the road was closed.
One resident shared their frustration on Kauaʻi Now’s Instagram account, claiming “KPD was called at least three time on this guy and acted like it was an inconvenience. … Explosions in the middle of the night/ early morning. Green lights flashing in people’s windows at 4:00 a.m. KPD did nothing!”
Other comments on Facebook have criticized the lack of communication from the police to the citizens in the area during the first hours when the road was closed.
“Sad situation on my street today,” Kauaʻi County Councilmember Felica Cowden wrote via Facebook. “Prayers and comfort to the family of the deceased.”
Cowden, who chairs the council’s public safety committee, told Kauaʻi Now on Sunday evening that she thanked the Kauaʻi Police Department for working to protect the island. But she added that in the last week there has been unacceptable violence in Waimea, Hanalei and Kīlauea.
“Leadership and public safety needs to better provide active and effective messaging to our trusting neighborhoods when their safety is at stake.”
The Kauaʻi Police Department first notified the public about a partial closure of Kīlauea Road at 8:30 a.m. on Saturday on its Facebook page, saying only it was closed “due to an active investigation.”
The next police update came at 6:15 p.m. on Saturday that the road had reopened, and all residents could return home, but with no explanation of what was going on. It was not until 8:53 p.m. that the police sent out a press release that they needed the public’s help in search of a man wanted as a suspect in a murder and a separate shooting.
Kauaʻi Now contacted the Kauaʻi Police Department on Sunday asking for more information about the manhunt and public safety, as well as their response to frustration by some in the community about the lack of timely communication. Police public information Tiana Victorino responded in an email: “To preserve the integrity of the investigation, and because this remains an active and ongoing case, we are unable to provide additional details at this time beyond what has already been released.
“We appreciate your efforts to provide accurate information to the community. Should additional details become available for release, the Kauaʻi Police Department will provide updates through its official communication channels.”
Kaua’i Now also contacted Mayor Derek S.K. Kawakami’s office, asking what message he has for North Shore residents and visitors who are worried about their safety during the manhunt. The county’s public information officer said in an email: “Adding in KPD PIO as this relates to them rather than us.”
