On October 10, 2018, the Department of Homeland Security (DHS) issued a notice in the Federal Register (83 Fed. Reg. 51114) proposing to prescribe how it determines whether an alien is inadmissible to the United States under section 212(a)(4) of the Immigration and Nationality Act (INA) because he or she is likely at any time to become a public charge and requested comments on or by December 10, 2018.

The ultimate totality of the circumstances determination must be designed to keep the rate of false positives less than half the total rate of positives, but does not have to be designed so as to minimize the rate of false negatives. This will decidedly impact how strong different kinds of evidence are for inference about the likelihood of any given alien becoming a public charge, as well as the appropriate levels for various thresholds.

To ensure consistency, objectivity, and more accurate determinations that are consistent with the criteria established in the INA, DHS should provide guidance on how a totality of the circumstances likelihood determination should be reached using evidence-based methods, namely using a base rate as a prior probability which can be updated based on the evidence about a given alien. Starting from the “inside view” of the evidence about a given alien rather than the “outside view” of base rates about the reference class of all aliens would likely lead DHS to significantly more false positive determinations.

DHS should estimate a base rates—both before the rule takes effect and again after a sufficiently long interval to account for disenrollment—for the proportion of aliens non-exempt from public charge inadmissibility who would be considered public charges. This base rate should then be considered the prior probability that an alien is likely to become a public charge. DHS should also estimate average levels of receipts, durations, and other kinds of evidence in the totality of the circumstances so that officials may compare any given alien’s evidence to average levels and make appropriate updates in the right direction.

Full comment available here.