Former Conservative leader Erin O'Toole is set to testify this morning at a federal inquiry into foreign interference, alongside three politicians who claim China has targeted them.

O'Toole said last spring that Canada's spy agency told him he had been the target of Chinese interference intended to promote false narratives online about his policies and discredit him during the 2019 election.

The Tories say security officials never informed the party about these concerns, which O'Toole blames for the loss of eight or nine seats. A government rapporteur found little evidence of such a link.

This afternoon, former Conservative MP Kenny Chiu is slated to take the stand, followed first by NDP MP Jenny Kwan and then Tory foreign-affairs critic Michael Chong. All three believe China has targeted them for advocating for human rights.

Ottawa expelled a Chinese diplomat last May after Canada’s spy agency alleged Zhao Wei was involved in a plot to intimidate Chong's relatives in Hong Kong.

Kwan says the Canadian Security Intelligence Service told her that China targeted her during the 2019 election in ways she can't disclose, in reprisal for her advocacy for human rights in Hong Kong and for the Uyghur Muslim minority in China.

Chiu claims Chinese authorities worked against him in the 2021 federal election after he had proposed a foreign-agent registry. Special rapporteur David Johnston said it's clear Chiu irked Chinese diplomats and that there was online misinformation about such a registry during the election, but he said it's unclear Beijing was behind those postings.

China strongly denies all claims it has meddled in Canadian democracy.

The ongoing hearings are part of the inquiry's work examining possible foreign interference by China, India, Russia and others in the last two general elections.

The commission of inquiry, led by Quebec judge Marie-Josée Hogue, expects to hear testimony from more than 40 people including community members, political party representatives and federal election officials.

Prime Minister Justin Trudeau, members of his cabinet and various senior government officials are also slated to appear at the hearings, which are set to conclude April 10.

An initial report of findings from the commission is due May 3.

The inquiry will then shift to broader policy issues, looking at the government's ability to detect, deter and counter foreign interference. A final report is expected by the end of the year.