The Northampton County panel deliberated for a little more than three hours Monday before convicting 22-year-old Ali Elijah Davis of Freemansburg of first-degree murder in the November 2007 deaths of 19-year-old Aleah Hamlin, 23-year-old Chanel Armour and 21-year-old Alphe Rene.
Authorities say Rene was targeted in retaliation for earlier killings in New Jersey.
Jurors return Tuesday to consider whether Davis should be sentenced to death or to life in prison.
In closing arguments Monday, defense attorney Brian Monahan said Davis is a "patsy" who wasn't involved in the shootings.
Another defendant, 33-year-old Lewis Gray of East Orange, N.J., is being tried separately.
