In general, people in the sports world keep their political leanings to themselves. Sure, there are a few guys who regularly speak out on political issues, but for the most part that's considered bad business. As Michael Jordan put it, "Republicans buy shoes too." That's why what the Phoenix Suns are doing is so amazing.
The Yahoo! article also quotes the Sun's star point guard, Steve Nash:
"I think it's fantastic," Nash said after Tuesday's practice. "I think the law is very misguided. I think it's, unfortunately, to the detriment of our society and our civil liberties. I think it's very important for us to stand up for things we believe in. As a team and as an organization, we have a lot of love and support for all of our fans. The league is very multicultural. We have players from all over the world, and our Latino community here is very strong and important to us."
And an official statement from the NBA Players Association:
The recent passage of the new immigration law in Arizona is disappointing and disturbing. The National Basketball Players Association strongly supports the repeal or immediate modification of this legislation. Any attempt to encourage, tolerate or legalize racial profiling is offensive and incompatible with basic notions of fairness and equal protection. A law that unfairly targets one group is ultimately a threat to all.
We applaud the actions of Phoenix Suns players and management and join them in taking a stand against the misguided efforts of Arizona lawmakers. We are consulting with our members and our player leadership to determine the most effective way for our union to continue to voice our opposition to this legislation.
Right on. Just speculating, but I'd imagine a good portion of NBA players have had their share of experiences being racially profiled. Though sports tend to be explicitly apolitical and implicitly conservative, perhaps in this case, the players' more overt political stance should not be so surprising.