Shurman said he was considering resigning for a year and his decision had nothing to do with the fact he was fired as the Tory finance critic in September after he claimed a $20,000 housing allowance for a residence in Niagara-on-the-Lake.
Shurman technically did not violate the rules, so all three parties quickly agreed to approve changes to make it clear only members whose ridings are more than 50 kilometres from the legislature are eligible for the housing allowance.
But Shurman then started claiming a mileage allowance for trips between Niagara and the Ontario legislature instead of between Thornhill and Queen's Park. Shurman claimed $6,292 in mileage for 2012-13.
"I don't have any sense of entitlement," he said in an interview with The Canadian Press. "I have a sense of honesty, fairness and integrity and I always follow rules."
Shurman said he sought clearance from legislative officials and was told he could claim mileage from his Niagara home.
"Who's going to get rich claiming mileage," asked Shurman, "and why would I do that without making sure I was absolutely on solid ground?"
However, PC leader Tim Hudak said he had made it clear to Shurman that he didn't agree with the mileage claims, even if they didn't technically violate the rules.
"I've set a certain standard that says we have to have a higher bar when it comes to respecting tax dollars," Hudak told reporters.
"When you make a decision that you're not living in your riding, I think you have to exercise some judgment on what you bill back to the taxpayer."
Hudak also made his position clear in a letter dated Dec. 3, but which Shurman said he received only Monday.
"In my mind and that of taxpayers, there is no distinction between the mileage claims and the housing issue you dealt with in September," Hudak wrote.
Hudak said Shurman may have found another loophole in the rules, but just as with the housing allowance, claiming mileage for trips to and from Niagara when he represents a Toronto-area riding was not consistent with the expectations of the public or the party.
"Taxpayers expect parliamentarians to hold themselves to a higher standard when it comes to expenses," added Hudak. "They expect us to respect their tax dollars."
In a statement released Tuesday morning, Shurman said after considering his situation for several months he concluded it would be a mistake to continue his political career.
"I will not be a candidate in the next provincial election," he wrote. "This decision is entirely my own and results from lengthy reflection and discussion with my family."
Shurman was first elected in 2007 and was re-elected in 2011.
His resignation is effective Dec. 31, which will leave two seats vacant in the legislature. Liberal Kim Craitor quit earlier this year.
Premier Kathleen Wynne has until March to call the byelection in Niagara Falls to replace Craitor, and until the end of June to call a special vote to replace Shurman.
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