Authorities say Robert Upton, 48, shot his brother-in-law, 47-year-old Aris Manoloules, in exchange for $165,000 from other members of the family, according to a a report today in the Boston Herald.
The incident happened inside Manoloules' Hyannis vacation home, the Herald reported.
Prosecutors say there had been bad blood between members of the family over a multimillion dollar inheritance.
According to the Cape Cod Times, Upton is scheduled to be sentenced Friday. His conviction carries a mandatory sentence of life in prison without the possibility of parole.