The Associated Press
CHICAGO- The gunman who went on a deadly shooting spree at a downtown law office was convinced a toilet he invented for truck drivers would transform his quiet life, his family said.Joe Jackson, 59, who drove trucks and taxis, also believed an attorney was trying to steal his invention, his family said.
"I believe he just snapped," son Darrin Jackson, 39, told the Chicago Sun-Times. "I believe he was just frustrated."
At the end of the bloody, 45-minute attack, three employees of the law firm - including one attorney, Michael R. McKenna, whose business card Jackson kept in his pocket - were dead and another wounded. SWAT snipers killed Jackson, shooting him in the face and chest as he held a hostage.
Investigators were trying to determine whether Jackson had been McKenna's client, police Superintendent Phil Cline said.
Jackson sought help from attorneys a few years ago to get something patented, his family told the newspaper in Sunday editions.
"He went to them, he trusted them," niece Brenda Jackson, referring to the attorneys. "He said, 'This is gonna pay off big.'"
McKenna researched it and told Jackson that it was already patented, the paper reported.
On Friday, Jackson forced a security guard at gunpoint to the 38th floor offices of intellectual property and patent law firm Wood, Phillips, Katz, Clark & Mortimer, locking and chaining the door, and demanded to see McKenna, police said.
McKenna, a patent attorney, rented office space from the firm.
The niece said someone at McKenna's office hung up on a phone call from him. He tried to enter the office at least one other time Friday, but was turned away because he did not have an appointment, police said.
"Under pressure ... who knows how you will react?" she told the Sun-Times. "You really don't know."
McKenna, 58, and Paul Goodson, 78, a retired teacher who worked part time in the office, both died from a gunshot wound to the head, the Cook County medical examiner's office said Sunday. Allen J. Hoover, 65, a partner at Wood, Phillips, died from a gunshot wound to the neck.
Jackson shot McKenna's paralegal, Ruth Zak Leib, in the foot, police said. Her husband, Larry Leib, told the Chicago Tribune that Jackson ordered his wife at gunpoint to identify McKenna.
"He didn't even know who Mr. McKenna was," he said. "He was so oblivious, she had to tell him who he was looking for. He had a gun to her head."
In a statement, John S. Mortimer, the firm's managing partner, called the attack "brutal and senseless." The firm will remain closed on Monday while staff members gather to remember their co-workers and receive grief counseling.
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The Associated Press left messages at numerous phone listings for Brenda Jackson in the Chicago area. A telephone listing for Darrin Jackson was unlisted.