"What is wrong with posting every dime," she said in an interview from Toronto. After being elected as the MP for Scarborough Southwest in 2008, Simson began posting her expenses online in exhaustive detail, even how much she spent on Christmas cards mailed to constituents.
Trudeau's plan for expense postings, to start Wednesday, is based on how cabinet ministers currently list travel and hospitality costs, with totals recorded for each event and trip but with no details or breakdown.
Simson, who was defeated in the last election, said when she refused to stop posting in 2010, she was forbidden by the Liberal Party whip from asking questions in question period and prevented from giving a member's statement, which meant she couldn't honour a soldier in her riding who was killed in Afghanistan.
At that time, the party was led by Michael Ignatieff
Simson thinks the current Liberal plan is “a step in the right direction. I'm actually buoyed by that. We have a baby step, we have our toe in the water, you know, let's kind of dive right in."
Trudeau, speaking to reporters Tuesday in the foyer of the House of Commons, said his plan is "the first step on what I hope will be a cascade of transparency and openness as the other parties try to outdo each other."
But at the moment, he admitted, in answer to a reporter's question, there would be no way to tell if an MP charged a $16 glass of orange juice, as former Conservative cabinet minister Bev Oda did in a move that led to her eventual resignation.
In June, on the final day of sitting before the House adjourned, a motion put forward by Trudeau to have all MPs post expenses online was defeated. But an NDP motion, mandating a study of how MPs claim expenses, including a closer look at Trudeau's suggestion, was passed unanimously.
Simson describes this action as "a stall tactic."
"What's to study," she said. "It's not their money."
Currently, all MPs and senators' quarterly expenses are posted online by House of Commons staff, but only in aggregate amounts, such as $80,000 for travel per quarter, and $25,000 for accommodation, with no explanations.
"I'm dying to see the results for the next fiscal year, how much spending has dropped, because this [change] is coming," Simson said.
Simson thinks MPs should even provide restaurant receipts when they claim their $80 daily allowance for being in Ottawa on parliamentary business, especially since MPs already get so many meals provided for them.
"The House of Commons, in the lounge — they have their hot lunch, free lunch, and there are events that you're going to where you're grazing all night," she said. "There are breakfast meetings, and if your committee met over lunch, they brought lunch in, dinner too.
"To me, that was non-taxable supplementary income."
Party discipline was also imposed on Liberal MP Scott Andrews who, along with Simson, posted his expenses online.
CBC News has obtained an email, written by the MP who represents the Newfoundland and Labrador electoral district of Avalon, sent just before the 2011 election to Ignatieff, who was the party's leader at the time.
"Michael, this has to stop," Andrews wrote, complaining he'd been denied giving a simple member's statement about an event in his riding. "My time in the penalty box has gone on long enough."
Reached Tuesday as he was travelling in a taxi from the Ottawa airport, Andrews said the shunning he experienced was only for a short time. "It was part of a systemic problem in the Liberal Party back then and hopefully now forced out and we're rebuilt.
"No study needs to be done on this,” he said, talking about the plan to study the issue. “It isn't rocket science, right?".
Green Party Leader Elizabeth May, the only MP who currently posts expenses, scans taxi slips and copies of her economy-class airline tickets and posts them. She even includes the bill from the office cleaner.
May has said there's nothing to stop Conservative and NDP MPs from unilaterally posting expenses in the same fashion she does. "They're afraid of their party bosses," she said.
She thinks MPs should choose to fly economy class, as she does, to save taxpayers' money.
One Conservative senator, Doug Black, has been posting his expenses, even the amounts claimed for printer ink and batteries, since he was appointed to the Senate in January,
Conservative Senator Bob Runciman says he intends to post his expenses by the end of the month. He told CBC News it's because he was appointed, rather than elected, and thinks senators should be held to a higher standard than MPs who can be kicked out of office by voters.
In response to Trudeau's remarks Tuesday, Conservative House leader Peter Van Loan issued a statement about the all-party committee that is studying how MPs disclose expenses: “Working with all parties on this initiative is very important, and we are looking forward to further discussions with them."
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