Keith's 11 Aug update: Sources report that the person (referenced below) who was told that they could not attend the JPL Planetary Science Summer School has now been told by NASA HQ that they can attend after all.
Keith's 7 Aug 10:11 am note: The following is posted in a Closed Facebook page "Young Scientists for Planetary Exploration". The group has 1,549 members. I was made aware of this issue last night in great detail before I asked to join the group. When my membership was approved just now I was confronted with a warning that I would be banned for life if I posted anything from this group. I was not aware of this restriction when I asked to join - only after the fact. This is an important issue that needs to be surfaced. I will not identify the individual who posted this. I expect to be banned momentarily. Oh well.
Keith's 7 Aug 8:11 pm note: I have been kicked out of the group (one would assume) for raising this issue. You're welcome. What is really odd is that Andy Rivkin, one of the people who run this Facebook group, violates their own rules with regard to publicly discussing content from within the group.
"I've been participating in this year's JPL Planetary Science Summer School for the past 9 weeks, and was told only today that I have been declined further participation in the program, and will be withdrawn from next week's session at JPL. The reason I was given was that my place of birth was in Hong Kong, regardless of the fact that my citizenship is Canadian. NASA regards all persons born in Hong Kong as Chinese Nationals, including those like myself who were born prior to the 1997 handover, were never granted Chinese citizenship, and have immigrated to other countries like Canada. After contacting some people to try to understand why I was informed of this so late, it has come to my attention that this is a NASA-wide issue (not just JPL or PSSS) that was enacted just today by the NASA HQ Security Branch."