Nate Silver dissects the Rasmussen poll showing that 70 percent of Arizonans favor the immigration measure signed into law by Gov. Jan Brewer last week:

But Rasmussen's portrayal of the law is very gentle. There's no mention of the provisions that liberals and civil libertarians find most odious: that the law would charge legal immigrants with trespassing for failure to carry documentation papers (although — note — this is already required under federal law); that it would give law enforcement officers new powers of detention (rather than mere "verification"); that it would allow officers, without a warrant, to arrest people who they suspected might be guilty of offenses that could lead to deportation, and that it would prohibit certain types of work-for-hire involving moving vehicles.

The Rasmussen poll says that 60 percent of Americans (and 70 percent of Arizonans) favor the new law, but how would those numbers change if people were read a longer or more complete description of the measure? Since there's been no other polling on the subject, we have no idea. It wouldn't shock me if the law indeed proved to be popular, especially in Arizona, if a fuller description were read. (Liberals, who uniformly seem to think that the law will be unpopular with certain key demographic groups, are a bit too sanguine about this). But this poll is so simplistic as to provide very little informational value.