It turns out that Sheriff Joe Arpaio, and his 'birther posse', based much of their claim that Obama wasn't born in the US on the fact that they have yet to find any evidence that his Mother left the country for Kenya and then returned with a newborn. Their position is that the only reason that they've failed to find these immigration records is because someone has stolen or destroyed them thus proving beyond a reasonable doubt that Obama was indeed born in Kenya and not Hawaii.
Of course, if Obama HAD been born in Hawaii then there WOULD be NO immigration records to be found. Did they ever consider that possibility? You know, the possibility that Obama and the officials in Hawaii are actually telling the truth?