1.   Fifty years ago, Tan might have been the focus of an overt form of bias, one where words or violence would have been used.

2.   Less overt forms of support by school officials may also be prohibited, depending on the degree of their involvement.

3.   Peruvian journalists have long been subject to arrest, bombings, wiretaps and other overt forms of censorship.

4.   In its more subtle form it is as damaging as in its overt form.