Investigators ran into a series of problems in trying to probe what came to be known as robocalls, allegations of misleading or nuisance calls across Canada in the 2011 federal election.

In a report released Thursday, Yves Côté, the commissioner of Canada Elections, said no charges would be laid following complaints of misleading or nuisance live calls and robocalls. He noted a number of problems that limited the ability to investigate the complaints.

In the end, it was difficult to sort out the legitimate calls made to encourage people to vote, or to vote for a specific party, from the calls alleged to be misleading or harassing.

The fair elections act would bring in some improvements, but leaves out a number of others. Here are three problems identified by investigators and how they may — or may not — be fixed under Bill C-23.

1. Limited information

National parties don't have to submit receipts and other documents to back up the expenses they claim for reimbursement from Elections Canada, so investigators didn't have access to contractual information between the national campaigns and telemarketing companies used to make the calls.

"The challenge lies in the limited information that must be provided to Elections Canada," the report said.

Candidates do have to submit supporting documents, but, the report noted, "the purpose for which a firm was retained, the phone numbers called, and the text of any calls made is not reported."

The Fair Elections Act would force the companies to keep scripts of live calls and recordings of robocalls, but parties still won't have to submit any records to back up their expense claims. Elections Canada officials have for years called for the ability to acquire those records, particularly because parties get 50 per cent of their spending reimbursed.

While the bill says the scripts and live calls will have to be held for a year, Minister of State for Democratic Reform Pierre Poilievre said Friday that he is asking for the bill to be amended to have the records held for three years.

2. Inability to compel witnesses

Elections Canada officials have asked repeatedly for the ability to go to a court and ask a judge to compel oral evidence from witnesses.

Côté's report notes that limitation, combined with the difficulty in getting production orders without significant progress in an investigation, made the robocalls probe harder.

"After a certain point, investigators had to rely on the voluntary participation of any concerned entity or person to obtain relevant information," the report said.

Marc Mayrand, the chief electoral officer, says many other regulatory agencies have that power, as well as provincial electoral agencies. Poilievre says police don't have that power and he isn't about to give it to Elections Canada.

"It's reasonable to expect that he [the commissioner] go to a judge and seek a court order to produce documents," Poilievre said. "That's what judges do… but I don't think that it's fair to give an election investigator powers that are not even available to police officers who are investigating the most violent and serious of crimes."

3. Robocall records

"There are no binding industry standards for the creation and retention of records by telephone service providers and telemarketing companies," Côté said in his report.

In the case of the complaints following the 2011 election, media reports the next year drew attention to the problem and elicited thousands of complaints. The vast majority of those complaints came nine months later, making the investigation harder.

The proposed bill will force the companies that provide calls to register with the CRTC, and Poilievre's new amendments will have them keep script and call recordings for three years. But they still won't have to keep the lists of phone numbers called, which would give investigators an additional avenue to pursue if new allegations surface in the future.

The investigators also pointed to technological challenges that allow callers to mask their phone numbers to prevent being traced.