Probably not but possibly. IANAL though and I think the HN questions are more about the technology rather than characterizing the innate "intelligence" of an applicant(if it can even be actually measured). I could see there being litigation from a minority group or a different culture saying that the standard IQ test as being racially biased towards white American people; thus, the test would fall under the civil rights act of 1964. There are also cultural differences that minimize the effectiveness of an IQ test being useful across cultural boundaries.

see: http://en.wikipedia.org/wiki/Race_and_intelligence#Test_bias

But really, why would you even want to use the result of a very flawed test that really does not show the true level of intelligence to hire someone? Assuming that the IQ test was perfect, intelligence is not the be all end all to performance at a company. Why not instead interview the candidates using performance tests in the specific areas that you are interested in?