From Fox News:
The Pinellas County Sheriff’s Office said in a news release that early Tuesday morning, 46-year-old John Heisler broke into the St. Petersburg home where the girlfriend, the teen and the teen’s younger sister lived. Authorities say when Heisler grabbed the woman, the new boyfriend called out for help, and the 18-year-old son emerged from his bedroom with a gun. The teen told police he shot his father after Heisling pointed the gun at him and his mother. . . .
No charges have been filed.
Authorities say the boy’s mother had obtained a temporary restraining order against Heisler . . .
A report from WTSP, the CBS affiliate in St. Petersburg, indicates that it was illegal for Heisler to have a gun, but somehow it hadn’t stopped him from acquiring one:
. . . According to Pinellas County records, Andrews was granted a domestic violence injunction against Heisler four months ago that was supposed to prohibit him from having guns or ammunition, granted her the home, and specified that Heisler could be there only under supervision of an officer to collect belongings. Heisler also was banned from the children’s schools, and where Andrews works.
UPDATE: Police have determined this shooting by the son was justifiable homicide. From News Channel 8 (WFLA):
Another dramatic case in Gresham, Oregon (September 6):
Police were called to the Rolling Hills Mobile Terrace and RV Park, 20145 N.E. Sandy Blvd., at 10:15 p.m. after numerous neighbors reported hearing gunshots.
More than a dozen officers arrived at the scene and found multiple people injured.
Investigators said four men entered a mobile home and attacked a 34-year-old man inside. Police said the man fought back, grabbed a pistol and shot two of the suspects.
One, a 25-year-old man, was pronounced dead at the scene. . . . .