What's up with the Poles? Is it a thing?
Just curious, asking as a Pole.
In the United States there has been a long history of discrimination against national origin, especially of recent immigrants. Poles were just used as an example here of a national origin.
Check out
http://en.wikipedia.org/wiki/Chinese_Exclusion_Act
http://en.wikipedia.org/wiki/Japanese_American_internment
for the most blatant forms.
It's probably an example of anti-racism law.
Poles are not a race though. It's only nationality.
True, but U.S. anti-discrimination law rarely speaks directly about race, and instead uses the broader phrasing "race, color, or national origin", which covers pretty much anything race- or ethnicity-based.
Polish is an ethnicity, and also national origin. In many places in Europe anti-racism laws don't just say "race", they say "race/ethnicity"
Of course, you can state no reason, and avoid leaving evidence of your real motivations, which might make it harder to prove: if you fire someone because you discovered they're Polish and you hate Poles, they can only win an unlawful-termination suit if they can prove that was the reason.