Originally Posted by
unagi1
The 'immigration' officers seem to be performing prescreening for those performing the traditional customs function.
What you succintly stated is exactly correct. And it's entirely by design.
With the agencies combined, I can see some of that happening, although I disagree with it, but a lot of it also went on when INS and Customs were separate.
My opinion is that it happened more at the land border than at airports prior to the merger. At the land border, INS and Customs inspectors were usually cross-designated and cross-trained to work both sides. It's more widespread now after the merger, certainly, because they are expected to understand and enforce both sets of laws.