This could be achieved in a number of ways. For example, poor swedes could be deported and rich immigrants could take their place - this would actually be more effective than halting immigration altogether.
Another form of issue dodging is when people suggest that immigrants are the issue without admitting that the situation is a complex combination of factors. One of the best predictors of criminality from a statistical viewpoint is gender. Of course, excluding all men from immigrating into our countries probably strikes most as inhumane :) To say the immigrant status of a person is to be specially focused on seems particularly convenient, but not humane.
edit: Its funny you're willing to accept taking gender into account statistically, but not the wealth of most immigrants.