2011
August 15
Bensalem police first come into contact with Cosmo DiNardo after someone calls to report him riding his ATV on the street.
2015
January
DiNardo is sworn in for his first one-year term as a mayor-appointed member of the Bensalem Drug and Alcohol Advisory Board.
June
DiNardo graduates from Holy Ghost Prep.
Summer
DiNardo meets fellow soon-to-be Arcadia freshman Sara Dinner at a concert. She said he made her uncomfortable and invited her and her friends back to his house. He then contacts her repeatedly on social media in ways she described as “aggressive and uncalled for.”
August
DiNardo enrolls at Arcadia University but only attends class there for one semester.
2016
January
DiNardo begins his second term as a member of the Bensalem Drug and Alcohol Advisory Board.
May
Police respond to a one-person ATV accident at the DiNardos’ Lower York Road property in Solebury. DiNardo said his injury was a broken ankle and he is taken to an unspecified hospital.
Bensalem police say DiNardo had 23 encounters with them before July 12.
July 12
DiNardo is involuntarily committed by his mother, Sandra DiNardo. He is evaluated by Lenape Valley Crisis Center before going to Doylestown Hospital. The length of his commitment is unclear.
Bensalem police say he had 17 encounters with them after the mental-health commitment.
October 23
DiNardo shows up uninvited to Holy Ghost Prep’s open house and is loud and disorderly.. He is escorted and banned from the campus.
November
Cosmo DiNardo is banned from the campus of Arcadia University after verbal interactions with several different students and staff when he returns to reenroll.
2017
January
DiNardo takes a one-credit class at Bucks County Community College.
February 9
Someone calls Bensalem Police to report a man with a shotgun. At 12:49 p.m., Officer Katharine Bailey pulls DiNardo over and finds him with a 20-gauge Savage Arms shotgun, which he is not legally allowed to possess because of his involuntary commitment. He is arraigned but not held in jail.
February 16
Preliminary hearing on gun charge continued from March 1 to March 21 at request of DiNardo’s lawyer Michael Kevin Parlow.
February 21
Preliminary hearing on gun charge continued from March 21 to March 29 at request of Magisterial District Judge Michael Gallagher.
March 24
Bensalem resident Adam Moore says he suffered injuries when his car was rear-ended by a vehicle driven by DiNardo on Hulmeville Road near Park Avenue.
March 29
Preliminary hearing on gun charge continued from March 29 to May 30 at the request of the commonwealth.
May
Attorney for Adam Moore files suit against DiNardo for the car accident.
May 30
Preliminary hearing on gun charge held at 8:15 p.m. at Judge Gallagher’s office. The charge is dismissed.
In the weeks before the killings: Acquaintances of DiNardo’s and friends of the victims said DiNardo bragged about having someone killed over a debt and made “scary insinuations.”