It's not like other countries don't deport undocumented immigrants either whether leftist or rightist so I don't see how when the US does it it's especially denouceable. [keep in mind, that Obama deported more than W].
I've lived in other countries [China as well as Eastern Europe], and it's not uncommon for regular police to either enforce immigration themselves or cooperate with the immigration office when people overstay their visas or sneak in.