My Korean colleagues have been asking me to explain this case to them, and I haven't been able to dig up enough reliable info to give much of an answer. I do think I can give a less inflammatory explanation for the shackling, though.

ICE sweeps mostly pick up undocumented laborers in the fields and factories. The people have nothing to lose by trying to run away, as they as just going to be deported anyway. So it stands to reason they would be restrained upon arrest. Documented workers on the other hand have a great deal to lose by further aggravating their situation. It is extremely unlikely that a documented worker would try to run away. However, I expect that ICE has to use the same procedures on all demographic groups to avoid charges racial discrimination.

Ah, ICE, so very sensitive to charges of racial discrimination.

Now that it's legal for ICE to racially discriminate do you think they will change their procedures? Or do you think ICE is more worried about the public perception of discrimination rather than the legality?