Canada's lobbying watchdog is ending an investigation into whether former Apotex head Barry Sherman violated lobbying laws when he hosted a party fundraiser at his home for Prime Minister Justin Trudeau's Liberal Party

In a letter sent to Duff Conacher of Democracy Watch, Lobbying Commissioner Nancy Bélanger said she is halting the investigation in the wake of Sherman's death.

"In light of Dr. Sherman's passing, the purpose of the investigation to ensure his compliance with the code can no longer be fulfilled."

Sherman and his wife Honey were found dead in the Toronto mansion in December in a case that shocked their friends and family. Police are investigating their deaths as are private investigators hired by the Sherman family.

The lobbying commissioner's investigation was triggered by complaints from Democracy Watch, which argued that Sherman, who was registered to lobby the federal government on behalf of Apotex, hosted a fundraiser for the Liberal party attended by Trudeau.

The group had also filed a complaint about Sherman selling tickets to another fundraiser that featured Finance Minister Bill Morneau.

In a press release, Conacher said he plans to challenge Bélanger's decision in court.