The added employees, known as on-site conformity advisers, or OCAs, checked and double-checked procedures at advanced polls and on election day to monitor whether polling officials actually knew and followed the procedures they were trained for.
The two ridings affected were Durham and Victoria. A third riding where a byelection was held, Calgary Centre, was used as a control and had no extra polling officials.
The hundred special advisers were veterans of the election system, either former returning officers or former polling officials. Some permanent employees Elections Canada's headquarters in Ottawa were seconded as well.
In documents obtained by CBC though an access to information request, Elections Canada says the conformity advisers were an "immediate response and temporary solution" to the procedural errors that were exposed during former Liberal MP Borys Wrzesnewskyj's attempt last spring to overturn the election results in the riding of Etobicoke Centre.
This project, the documents say, was intended to reassure voters "that trust and the integrity of the Canadian electoral system are very important values for Elections Canada."
Wrzesnewsky lost Etobicoke Centre by only 26 votes, but he alleged that almost 200 errors occurred across a sample of 10 polls chosen for the court case.
In May, a judge voided the election in Etobicoke Centre, discarding 79 ballots due to missing or erroneous paperwork that often failed to record basic details about voters who showed up without ID. The fact that so many procedural mistakes could be uncovered in just 10 polls seemed to indicate that similar errors could have been spread across the entire riding.
Although the Supreme Court of Canada reversed the lower court decision in October and ruled that the right to vote almost always supercedes any procedural error, Elections Canada had to face the fact that in many cases in Etobicoke Centre, rules were flouted or ignored by its own polling officials.
John Enright, a spokesman for Elections Canada, said the advisers in the byelections were meant to provide data to Chief Electoral Officer Marc Mayrand to see how his training procedures were being interpreted.
"The lessons learned will be applied moving forward," he said. "If we find that a certain block of our training is not being understood, that would mean we have to rejig our training."
Enright explained that the approximately 200,000 hirees who are paid to work just a few days every election year have only three hours of training. Even if the've worked elections before, the procedures are complex.
There's no word yet whether the advisers will become permanent fixtures on elections day. A report is being prepared for Mayrand, Enright said, and will either be released on Elections Canada's website or delivered by Mayrand to a parliamentary committeee.
Enright said he's not certain about what the cost would be of putting an adviser at most polling stations, but estimates that about $15,000 a riding might be the right figure. This would mean that the potential cost of ensuring voters that their votes won't be discounted due to procedural errors could add up to more than $5 million.