As others have noted, there is not a lot of context mentioned in this article. I think the officer may have had some prior knowledge that prompted the questions he asked this man.
I am a progressive, but every country has the right, even the duty, to make laws regarding the status of anyone inside its national borders. I believe that there’s a way to accommodate the children of immigrants who came here very young because of their parents. They don’t deserve to be kicked out of a country that is the only home they’ve ever known. But adults who come here illegally should be prosecuted and deported. I’d suggest that parents of children brought here, if they have not committed other criminal offenses besides their documentless status, be allowed to stay, also. This seems the only humane approach.