Bail Increased for William “Billy” Sinclair

Published on June 13, 2026

LĪHU‘E – William “Billy” Sinclair, 51, of Kīlauea, remains in custody in connection with a homicide and attempted homicide investigation.

Following judicial review related to evidence recovered during the investigation, Sinclair's bail was increased from $500,000 to $1.5 million.

Investigators recovered multiple firearms and related items during the course of the investigation. On June 12, 2026, Sinclair was arrested for the additional offenses (20 counts) of Ownership or Possession of Firearms, Ammunition and Dangerous Weapons Prohibited. Additional offenses may be considered as the investigation continues and evidence is reviewed.

Members of the public who may have information related to the investigation are encouraged to contact Detective Caspillo at (808) 241-1680. To remain anonymous, contact Crime Stoppers Kaua‘i at (808) 246-8300, submit a tip at crimestopperskauai.org, or use Crime Stoppers Kauai P3 Tips Mobile App. Crime Stoppers Kaua‘i is a non-profit organization that offers cash rewards of up to $2,000 to anyone furnishing anonymous information that leads to an arrest.

This remains an active investigation, and no additional information is available at this time.

William “Billy” Sinclair, 51, of Kīlauea.

###