This time, an odd coincidence lead to his conviction and one-year sentence.
Last June, Ballem was sentenced to four months in jail for uttering threats to cause death or bodily harm. He posted a letter on the WCB's door addressed to the employee who denied his claim.
The letter threatened the case worker and called his family "sitting ducks."
Last Nov. 29 -- not long after Ballem's release -- a maintenance worker at the Centre Square Mall, Dean Harvey, received a phone call there from someone asking to pass along a threat to the Workers Compensation Board. The WCB is located in the mall's office tower.
The caller talked about destroying the WCB by Dec. 1, and said: "Roger Warren didn't do it, we're still here." Two others overheard the conversation over two-way radios.
At same time, the wife of the case worker Ballem threatened was shopping in the YK Centre Mall.
She saw Ballem talking on a payphone in the mall and listened carefully to what he said.
Last week, she testified to hearing him say: "They've ruined three more of our guys and we're going to take them out."
After hearing about this, RCMP Const. Christian Vezina went to the mall and jotted down the numbers on the two payphones.
He then called Les Chapman at NorthwesTel.
Chapman was able to determine that a call from the payphone was made to Centre Square Mall's maintenance line during the specified time.
Thomas Ballem was arrested the same day and later charged with uttering a threat to cause death and bodily harm to personnel at the WCB, uttering threats to destroy property at the WCB and breach of probation.
Because of a falling out with his lawyer, Ballem represented himself at trial. He said he was at home rearranging his furniture that day.
But he can't prove his innocence, he said, because his "old lady" was out and "the cat don't talk."
The 58-year-old man told the court he's been trying to figure out who committed the crime. "To me, it sounds like someone on dope," he said. "It's got to be."
Ballem said he had no reason to jeopardize his freedom by making threats again.
The evidence against him is circumstantial, said Ballem. "Circumstantial evidence is nothing but a bunch of words that proves absolutely nothing."
Crown prosecutor Shannon Smallwood cross-examined Ballem, and asked him about the claim he filed in 1992 because of work-related injuries. His claim was eventually denied after 10 years. The claim was denied in December 2001 -- the same time of year the threats were made.
Judge Michel Bourassa agreed with Ballem that the evidence against him is circumstantial.
But he said all the evidence coupled with NorthwesTel ability to place the accused at the phone booth at the material time proved the case beyond a reasonable doubt.
Smallwood asked for an 18-month sentence, considering his past history of uttering threats.
More than 100 people were affected by the threat, she said, and some of them were very distressed.
Ballem asked for a mistrial and said he'd "just as soon not be sentenced and go back to work." He added "nobody's been hurt over this."
Ballem's claim that the threat caused no harm is "incredible," said Bourassa.
It's not uncommon to hear about disgruntled workers acting out their threats, said Bourassa. "I understand the fear, because there is a reality to those kinds of threats."
He convicted the man on all three counts, and sentenced him to one year in jail and two months probation.
Ballem is forbidden from having any contact with WCB or its employees.
On his way to jail, Ballen appeared to be making another threat.
He told the judge he "can't be responsible for what my wife does" when she finds out he's in jail.