OTTAWA -- A three-year investigation into allegations of fraudulent robocalls during the last federal election has found no evidence of intent to deceive voters nor any evidence of an orchestrated scheme beyond Guelph, Ont.

A long-awaited report from commissioner of elections Yves Cote will come as vindication for the Conservative party, which has faced a cloud of suspicion for years over widespread reports of non-party supporters being directed to the wrong polling stations in the final days and hours of the hard-fought vote on May 2, 2011.

"Having carefully examined all of the evidence, the commissioner found no reasonable grounds to believe that an offence under the (Elections) Act has been committed," Cote's 32-page report, posted Thursday, flatly asserts.

The conclusion is supported by an independent review by Louise Charron, a former Supreme Court justice who was paid by Elections Canada for her expert opinion.

Pierre Poilievre, the minister for democratic reform, said the report proves the Conservative party ran "an honest and ethical campaign" in 2011.

"We followed all of the rules and we won fair and square," Poilievre said Thursday before delivering a speech on controversial new electoral reforms proposed for the 2015 vote.

"That is what we've been saying all along and those who've been making baseless smears ever since have been once again proven wrong in the process."

Cote's investigation is separate from robocall allegations during the same election in Guelph, where a young Conservative campaign staffer, Michael Sona, faces Elections Act charges for his alleged role in calls that impersonated Elections Canada.

Despite tens of thousands of citizen complaints after media reports surfaced regarding the investigation in 2012, the commissioner said it all boiled down to 1,726 complainants in 261 electoral districts.

"Overall, no discernible pattern of misdirection, such as a predominant calling number or constellation of predominant calling numbers, was noted that would suggest a potential breach of the Act," the report says.

That is not to say some citizens weren't sent to the wrong polling stations.

Cote castigates the Conservative party for going ahead with calls to electors informing them of their polling station after Elections Canada had expressly told all parties not to do so. And his report states these calls went ahead "despite, at least in the case of one party, their knowledge that a small percentage of electors would be given incorrect information."

Elsewhere in the report that party is identified as the Conservative Party of Canada.

That has some critics, including the watchdog group Democracy Watch, saying Cote should have referred the matter to prosecutors to let them ascertain whether charges were warranted.

However the report states that "it is not sufficient to find evidence of misdirection of an elector. There must be evidence of intention to prevent the elector from voting, or by some pretence or contrivance, to induce the elector to vote or not vote for a particular candidate.

"No such evidence was found."

Cote says as a result, he won't be referring the matter to the federal director of public prosecutions and the investigation is effectively over.

The report says the investigation was complicated by the amount of time it took for many people to report the suspicious calls, which caused memories to fade. Extensive media coverage may have also coloured recollections, says the report.

And potential witnesses and certain "entities" also did not fully co-operate with investigators.

"A significant amount of investigative effort was used in attempting to obtain the co-operation of individuals, political parties, telemarketers and telephone service providers," says the report.

"Those who agreed to co-operate sometimes took considerable time to come to that decision or to schedule a response to investigators' requests for meetings; in some cases, they declined to co-operate fully."

Cote says Elections Canada needs the power to compel testimony -- something the Conservative government left out of its controversial new elections overhaul despite calls last year for increased investigative powers.

Charron, in a four-page appendix to the report, mentions the "inordinate delays and at times inexplicable resistance to providing the requested information," to investigators.

"I am unable to say if the result of this investigation might have been different in a world where none of these investigative challenges existed," concludes the former Supreme Court justice.

"My overall sense is that it would not be."