The party has complained to Quebec provincial police and the office of Quebec's chief electoral officer.
A spokesperson for the chief electoral officer said his office is studying the complaint to determine whether there has been an infraction under Quebec's electoral act.
In a statement issued Monday, a day before Quebecers go to the polls, the Liberal party said voters in the Quebec City region have been receiving robocalls claiming to be coming from the party.
The statement said the alleged fraudulent calls, made exclusively in English and directed at French-speaking voters in the hotly-contested riding of Taschereau, are clearly coming from Liberal "ill-intentioned opponents."
"The information they gave is completely inaccurate," Liberal party spokesperson John Abecassis said. "What is worrisome is, first of all, we didn't make these calls."
Abecassis said the automatic message directs electors to call another number in the Quebec city area. The voice mail message at that number greets callers in English first, followed by French. It identifies the number as belonging to the Quebec Liberal party and invites them to leave a detailed message.
"We don't know what is going to be the follow-up with [electors] who, with good intentions, called back and wanted to find out maybe where to go vote or anything," Abescassis said. "When an election is this tight, we find these kinds of manoeuvres, very, very deceiving."
"The question is, what is the objective behind them, and more importantly, why is it being done under the cover of anonymous phone calls like this," he added. "Who is it destined for, and also — who is behind it?"
The redrawn Taschereau riding is considered one to watch in the Sept. 4 election — one shaping up to be a three- or even four-way race.
The Liberal candidate, Quebec's widely-respected natural resources minister Clément Gignac, switched ridings in an effort to unseat the last remaining PQ member in the Quebec City region, Agnès Maltais. But it's the Coalition Avenir Québec that is polling ahead of the two old parties across the region, and the Taschereau riding is also the best hope in Quebec's capital city for the left-of-centre sovereigntist party, Québec Solidaire.
The Liberal party said a similar strategy to the one allegedly used in Taschereau has been reported in the Laval region, where people using an aggressive tone have been calling voters repeatedly and falsely claiming to represent the party.
Robocall controversy in federal vote
Political parties regularly use automated robocalls and live calls to identify voter support and contact people during an election campaign, and Denis Dion, a spokesperson for the office of Quebec's chief electoral officer, made it clear the practise is perfectly legal.
"It is legal to use robocalls, as long as [the source] is identified under the name of the official agent of the party or the candidate," said Denis Dion.
Dion added there is no provision in Quebec's electoral act that covers fraudulent calls, although his office will be looking into whether some other provision of the act has been breached.
The practice of robocalling became controversial in the 2011 federal election.
Investigators found that calls wrongly claiming to be from Elections Canada redirected voters to a polling station they couldn't use. The calls were traced to a cellphone registered to "Pierre Poutine."
Investigators have not determined who ordered the calls.