In this opinion, the Ninth Circuit explains the evidentiary standard for inadmissibility under INA § 212(a)(2)(C) for being an alien who the consular officer or the Attorney General knows or has reason to believe . . . is or has been an illicit trafficker in any controlled substance or in any listed chemical (as defined in section 802 of Title 21), or is or has been a knowing aider, abettor, assister, conspirator, or colluder with others in the same. The question is who must have the necessary “reason to believe” and at what time.
The court held that the reason to believe must be collectively known by the officials adjudicating the question of admissibility. At the time of entry, that would be the CBP inspector and any other appropriate officials within one of the DHS agencies. If the inspector does not admit the noncitizen and instead puts him or her into removal proceedings for inadmissibility, then the immigration judge (or BIA, once on appeal) is the official that must have reason to believe. In the latter situation, the IJ and BIA are not limited to the facts known at the time the noncitizen's inspection at the port of entry. Later obtained evidence, the respondent's testimony, and even expert testimony may be considered. The court then will review the decision of the IJ and the BIA for substantial evidence.
The court also found that, although the credibility of the noncitizen was important, it did not need to deem the testimony credible in the absence of an explicit adverse credibility finding.
Read the decision at http://www.ca9.uscourts.gov/datastore/opinions/2011/07/14/06-70635.pdf