The people who will be best able to know who the people involved in these regimes are when they come into a freer country like Canada are other people from that country.
If you're going to screen Venezuelan refugees, you likely need input from other Venezuelans who are already in the country. This is why I think so many people say they're part of the Cuban Communist Party or the Venezuelan United Socialist Party, people who distribute food and withheld food aid for political reasons in Venezuela, who have been able to get to the U.S. or Canada. They have been able to get through because there were no other Venezuelan or Cuban immigrants who were paying attention or looking at those files. It's much more likely that people from those countries will know who is involved in criminal activity than people from other places.