Should Citizens Report Immigrants?

Roberto at Of América, notes and comments the question from NPR to presidential candidates: 

“If there is one issue that has challenged presidential candidates of both parties in Iowa this year, it is immigration, and the Democratic contenders were confronted with it again Tuesday, in a provocative way. Should American citizens, they were asked, turn in someone they know to be an illegal immigrant?” 

Even after Hillary Clinton responded that citizens should not be “enforcing the broken laws of our federal immigration system”, NPR’s Steven Inskeep continued the line of questioning by asking, “If a citizen witnessed some other kind of crime, wouldn’t you want them to report it?”

This is tempting the opening of the proverbial 'can of worms.'