A possession conviction, like any other facts, can be considered by the
government in making the Reason To Believe illicit trafficking determination, but it obviously standing alone is not sufficient because it provides no RTB of trafficking, just use. See Matter of Winter, 12 I. & N. Dec. 638 (BIA 1968); Matter of Seda, 17 I. & N. Dec. 550 (BIA 1980), that are not exactly on point but may help by analogy. They basically say that if a criminal case results in a final disposition that does not constitute a CMT, the government cannot go behind that disposition and look at " e.g., a vacated plea " and use that as an oral admission equivalent to a conviction for inadmissibility purposes. Immigration counsel can argue that since the DHS cannot use a court disposition that does not establish inadmissibility as a conviction-based ground of inadmissibility, it also cannot use it to establish a different crime-related ground of inadmissibility either, the RTB ground.

Immigration counsel can argue that a noncitizen cannot be found inadmissible, under INA 212(a)(2)(C)(i), for reason to believe he or she was an illicit trafficker, on the basis of an arrest for unlawful possession with intent to deliver cannabis where the charges were dismissed on motion of the prosecutor's office for lack of sufficient evidence.

Where the evidence fails to establish anything more than a mere suspicion, then a reason to believe finding is unsupported as a matter of law. According to the Foreign Affairs Manual, reason to believe means more than a mere suspicion by a consular officer that an applicant may be or have been involved in drug trafficking. 9 FAM 40.23 N2. FAM directs consular officers to decide whether a probability, supported by evidence such as a conviction, an admission, a long record of arrests with an unexplained failure to prosecute by the local government, or several reliable and corroborative reports exists before making a finding of inadmissibility for reason to believe. Id. A determination of reason to believe must be based on reasonable, substantial and probative evidence. Alcarcon-Serrano v. INS, 220 F.3d 1116, 1119 (9th Cir. 2000). Respondent has a right to present evidence to rebut the charge of reason to believe. Pronsivakulchai v. Gonzales, 461 F.3d 903 (7th Cir. 2006). Reason to believe is equated with probable cause. Matter of U-H-, 23 I&N Dec. 355, 356 (BIA 2002). Therefore, an officer must apply a higher standard than a mere suspicion and assess independently evidence before making a finding of inadmissibility for reason to believe. Thanks to Sara Dady.