What is the test for forfeiture of a vehicle used to transport an illegal alien?

Every alien is presumed to be an immigrant until she establishes to the satisfaction of the immigration officers, at the time of application for admission, that she is entitled to nonimmigrant status. 8 U.S.C. 1184(b); Jain v. INS, 612 F.2d 683, 686 (2d Cir.1979), cert. denied, 446 U.S. 937 (1980). Testimony by an immigration officer having personal knowledge of the facts concerning an alien's status constitutes prima facie evidence that the alien had not received prior official authorization to come to, enter, or reside in the United States. 8 U.S.C. 1324(b)(5)(C). In a forfeiture action, the claimant must then rebut the government's showing of probable cause that the vehicle used in conveying the alien is subject to forfeiture. 8 U.S.C. 1324(b)(5).