The First Step Act of 2018 ("FSA") provides that an eligible prisoner "shall earn" time credits if he participates in the FSA's flagship recidivism-reduction programming. 18 U.S.C. § 3632(d)(4). The FSA further provides that a prisoner "is ineligible" for time credits "if the prisoner is serving a sentence for a conviction under any" of sixty-eight designated provisions of the United States Code.

The important question presented is whether a prisoner convicted of both an eligible and ineligible offense, who (i) finished serving the sentence imposed on the ineligible offense, and (ii) is serving out only the concurrent sentence imposed on his eligible offense, is eligible for time credits.

The second question presented is whether, in a case shaped by Chevron but decided after Loper Light, the Second Circuit's uncritical acceptance of an agency's interpretation of the FSA, amounting to deference in fact if not in name, violates Loper Light's clear mandate and spirit.

Whether a prisoner serving concurrent sentences for both eligible and ineligible offenses is eligible for First Step Act time credits under 18 U.S.C. § 3632(d)(4)