Serious drug-related offenses will generally bar a foreign national from being allowed to enter the U.S. and can be the basis for deportation and inadmissibility. However, it is not necessary for the U.S. immigration services to show that there has been a conviction for crimes like drug trafficking. Rather, U.S. immigration services can use a much lower standard called "reason to believe." This standard comes from section 212(a)(2)(C) of the Immigration and Nationality Act which states that:
"Any alien who the consular officer or the Attorney General knows or has reason to believe — (i) is or has been an illicit trafficker in any controlled substance or (ii) is or has been a knowing aider, abettor, assister, conspirator, or colluder with others in the illicit trafficking in any such controlled or listed substance or chemical, or endeavored to do so . . . is inadmissible."
As noted, the "reason to believe" does not require proof of a conviction for drug trafficking. It is sufficient that the immigration services have a "reason to believe." On the other hand, a conviction for drug trafficking will almost always create a "reason to believe" that is sufficient to deny entry and be the basis for deportation.
So, what does the "reason to believe" standard require? As reported and discussed extensively in this case decision, Garces v. US Atty. Gen., 611 F.3d 1337 (11th Cir. 2010), the State Department has this definition of how "reason to believe" can be established:
"'Reason to believe' might be established by 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. The essence of the standard is that the consular officer must have more than a mere suspicion — there must exist a probability, supported by evidence, that the alien is or has been engaged in trafficking."
From this, we can see that there are several ways to establish "reason to believe." First, as noted, a conviction for drug trafficking will rise to "reason to believe." Second, a long record of arrests can give rise to "reason to believe." Third, reports from eyewitnesses and police officers reports can provide a basis rise to "reason to believe" if there are several accounts that are corroborated and reliable.
Because this is the standard, close attention must be paid to facts when defending against inadmissibility or deportability because of reason to believe. The Garces case linked above is a good example since, in that case, the foreign national's attorneys were able to argue that there had been no "conviction" even though there had been a drug-crime-related voluntary plea of guilty entered in a Florida criminal case. For technical legal reasons, the guilty plea was not considered a "conviction" for purposes of immigration law. In different cases, the reason to believe can be attacked on the other grounds mentioned above. What actual evidence is available on which to base the reason to believe? Is that evidence reliable and corroborated? Is there more than one eyewitness account, etc.?