                               In the

    United States Court of Appeals
                 For the Seventh Circuit
                     ____________________
No. 19‐3517
UNITED STATES OF AMERICA,
                                                   Plaintiff‐Appellee,
                                 v.

VINCENT CORNER,
                                               Defendant‐Appellant.
                     ____________________

         Appeal from the United States District Court for the
                   Western District of Wisconsin.
             No. 07‐cr‐104 — Barbara B. Crabb, Judge.
                     ____________________

        ARGUED JULY 8, 2020 — DECIDED JULY 24, 2020
                 ____________________

   Before WOOD, BARRETT, and ST. EVE, Circuit Judges.
    PER CURIAM. Vincent Corner violated the conditions of his
supervised release, and he was sentenced to 18 months’ im‐
prisonment followed by 42 months’ supervised release. Cor‐
ner later moved for a reduced sentence under section 404 of
the First Step Act of 2018. The district court did not assess
Corner’s eligibility for relief under the Act, explaining that it
would not lower his sentence regardless of his eligibility be‐
cause he had violated the terms of his release. Corner appeals,
2                                                   No. 19‐3517

arguing that it was procedural error for the district court to
deny relief without first determining whether the Act applied
to his sentence and what the new statutory penalties would
be. We agree, so we vacate the judgment and remand for fur‐
ther proceedings.
    While serving a term of supervised release for possessing
with intent to distribute 11 grams of cocaine base (i.e., crack),
21 U.S.C. § 841(a)(1), Corner violated the conditions by using
and possessing illegal drugs, failing to comply with drug test‐
ing, and lying to his probation officer about his inability to
maintain employment. Because Corner had tested positive for
controlled substances more than three times in one year, the
district court determined that revocation of his supervised re‐
lease was mandatory. See 18 U.S.C. § 3583(g)(4). The court
noted that the statutory maximum for Corner’s reimprison‐
ment was three years, id. § 3583(e)(3), and that another term
of supervised release of 60 months, minus the revocation sen‐
tence, could be imposed, id. § 3583(h). It sentenced Corner to
18 months’ imprisonment (half of the statutory maximum)
and 42 months of supervised release.
    Shortly after Corner was sentenced, Congress passed the
First Step Act of 2018, which empowers district courts to re‐
duce a defendant’s sentence by applying the Fair Sentencing
Act of 2010 retroactively. First Step Act of 2018, Pub. L.
No. 115–391, § 404(b), 132 Stat. 5194. The Fair Sentencing Act,
in relevant part, modified 21 U.S.C. § 841(b)(1)(B)(iii)—under
which Corner was convicted—by reducing the statutory min‐
imum penalties and increasing the amount of crack necessary
to trigger those penalties from 5 grams to 28 grams. Fair Sen‐
tencing Act, Pub. L. 111‐220, § 801, 124 Stat. 2372.
No. 19‐3517                                                                3

   Corner moved under 18 U.S.C. § 3582(c) for a reduction of
his revocation sentence and term of supervision based on
§ 404 of the First Step Act.1 Pursuant to a standing order in the
Western District of Wisconsin, the district court appointed
counsel for Corner. Corner argued that, although his current
sentence was for violating the terms of his supervised release,
he was eligible for a reduction under the Act because his orig‐
inal conviction was for violating 21 U.S.C. § 841. He asserted
that a reduction was warranted to further Congress’s intent in
passing section 404 by reducing the inequity between his total
sentence and the sentences of similarly situated powder‐co‐
caine defendants. It would also promote fair sentencing for
Corner, whose 140‐month sentence was greater than neces‐
sary to promote the goals of sentencing because it was im‐
posed based on a now‐superseded guideline range.
    Corner then pointed out, correctly, that, had the Fair Sen‐
tencing Act applied at the time of his original sentencing,
there would have been three material differences. First, the
statutory range is now 0 to 20 years’ imprisonment; at the time
of sentencing, it was 5 to 40 years. Second, his original crime
now carries a maximum revocation sentence of two years’ im‐
prisonment; he was sentenced to 18 months’ imprisonment
with the understanding that his crime carried a maximum
revocation sentence of 3 years. And third, his underlying of‐
fense now carries a minimum of three years’ supervised re‐
lease, but the additional 42 months of supervision that the
court ordered to follow his revocation sentence was imposed

    1 This court recently held that the First Step Act itself authorizes such
motions, so a petitioner for a reduced sentence under section 404(b) does
not need to invoke § 3582 as a “vehicle” for relief. United States v. Sutton,
962 F.3d 979, 984 (7th Cir. June 23, 2020).
4                                                   No. 19‐3517

with the understanding that the underlying drug offense re‐
quired a minimum of four years’ supervised release.
    The government argued in response that, because Corner
had completed his sentence for the crack conviction, he was
not eligible for relief under the First Step Act with respect to
the revocation sentence. Even if Corner were eligible, it ar‐
gued, his repeated violations of the terms of his supervised
release warranted the 18 months of reimprisonment and the
additional 42 months’ supervision.
    The district court denied Corner’s motion. It first con‐
cluded that deciding whether he was eligible for relief under
the First Step Act was unnecessary because the court “would
deny his request for a reduction” even if he was. The court
cited Corner’s untruthfulness with his supervising probation
officer, his refusal to comply with drug testing, his persistent
use of illegal drugs, and his inability to hold down a job. These
were the same grounds it had given for the revocation sen‐
tence. Further, the court noted that the 18‐month prison term
was permissible because it did not exceed the new maximum
revocation penalty of two years. Finally, the court, without
further explanation, declined to reduce Corner’s new period
of supervised release, but it said it would later consider a
modification if his conduct on supervision warranted it.
    Corner completed his 18‐month revocation sentence and
began his 42 months of supervision in March 2020. On appeal,
Corner argues that the district court committed reversible er‐
ror by failing to decide his eligibility under the First Step Act
before denying his motion for a reduced sentence. By omit‐
ting that step, Corner asserts, the court failed to determine
what lower statutory penalties would have applied to his
original conviction if the Fair Sentencing Act had been in
No. 19‐3517                                                    5

place, and therefore it had no baseline from which to exercise
its new discretion. We conclude that a district court’s discre‐
tionary determination whether to grant a petitioner’s motion
for a reduced sentence under the First Step Act must be in‐
formed by a calculation of the new sentencing parameters.
    Section 404 of the First Step Act provides that anyone who
is eligible for relief under the Act can move for a reduced sen‐
tence and directs district courts to consider the motion with
reference to the statutory guidelines imposed by the Fair Sen‐
tencing Act. From there, the court’s decision is discretionary;
section 404(c) makes clear that the court is never required to
reduce a sentence under section 404(b). What, procedure, if
any, a court must follow before making that decision, is up for
debate: Courts generally agree that plenary sentencing is not
required, see United States v. Foreman, 958 F.3d 506, 510
(6th Cir. 2020) (collecting cases); several courts say that con‐
sideration of the 18 U.S.C. § 3553(a) sentencing factors is ap‐
propriate; see United States v. Shaw, 957 F.3d 734, 740 (7th Cir.
2020); United States v. Harris, 960 F.3d 1103, 1106 (8th Cir.
2020) (collecting cases); and some courts have determined
that First Step Act decisions are reviewable for procedural
and substantive reasonableness. See Foreman, 958 F.3d at 515;
Harris, 960 F.3d at 1106–07. Few cases, however, discuss more
generally how a district court should proceed when asked to
reduce a sentence under section 404.
    Corner frames the issue on appeal as an “eligibility” ques‐
tion, and the government follows suit, but eligibility is simply
the gateway to resentencing under the First Step Act and is
determined by “the statute of conviction alone.” Shaw, 957
F.3d at 739. The district court’s discretionary decision to grant
or deny the request for a reduced sentence is the main event.
6                                                     No. 19‐3517

So the question here is less about determining eligibility than
determining the consequences of eligibility—the new statutory
penalties—and whether a district court can reasonably exer‐
cise its discretion without doing so. The text of the First Step
Act, however, suggests that it cannot.
    The statute contemplates a close review of resentencing
motions: section 404(c) states that a person cannot seek relief
under the Act more than once if the first motion was “denied
after a complete review of the motion on the merits.” First Step
Act § 404(c) (emphasis added); see also Shaw, 957 F.3d at 743;
United States v. Boulding, 960 F.3d 774, 784 (6th Cir. 2020). The
requirement that a motion under § 404 receive a “complete
review” suggests a baseline of process that includes an accu‐
rate comparison of the statutory penalties—and any resulting
change to the sentencing parameters—as they existed during
the original sentencing and as they presently exist. “A resen‐
tencing predicated on erroneous or expired guideline calcula‐
tion,” or a decision to decline resentencing without consider‐
ing at all the guidelines, “would seemingly run afoul of Con‐
gressional expectations.” Boulding, 960 F.3d at 784.
    This is comparable to the procedural requirement that a
district court correctly compute the applicable sentencing
guidelines range before deciding, in its discretion, what sen‐
tence to impose. See Gall v. United States, 552 U.S. 38, 51 (2007).
Although a court can impose a sentence outside a properly
calculated range, the guidelines “must be considered seri‐
ously and applied carefully.” United States v. Lopez, 634 F.3d
948, 953 (7th Cir. 2011). And a failure to properly calculate
and consider the guidelines amounts to a reversible proce‐
dural error. United States v. Griffith, 913 F.3d 683, 687 (7th Cir.
2019).
No. 19‐3517                                                     7

    Not considering the lower statutory penalties now appli‐
cable to Corner’s offense of conviction was procedural error
for the same reason: the court decided what to do without first
determining the parameters of what it could do. The court’s
uninformed exercise of discretion, therefore, was divorced
from the concerns underlying the Fair Sentencing Act (appli‐
cable to Corner through the First Step Act), which sought to
redress the extreme inequity between sentences for crack and
powder cocaine offenses deemed irrational and unfair by
Congress. The district court declined to entertain concerns
about the fairness or equity of Corner’s revocation sentence,
even though he already served a prison sentence that was, by
current standards, substantially longer than necessary to pro‐
mote the goals of sentencing.
    The government argues that, even if the district court
erred by declining to consider the modified statutory penal‐
ties, this court should nevertheless affirm because any error
was harmless: the court would have imposed the same sen‐
tence, and, in any event, Corner has now finished serving his
revocation sentence. True, a procedural error (such as a mis‐
calculation of the applicable guidelines range) is not reversi‐
ble if it’s clear that the court did not rely on it when selecting
the sentence. United States v. Snyder, 865 F.3d 490, 500 (7th Cir.
2017). In fact, we encourage district courts to exercise discre‐
tion under § 3553(a) rather than impose a guidelines sentence
when faced with a tricky and disputed guidelines calculation.
See United States v. White, 883 F.3d 983, 987 (7th Cir. 2018). But
we “must be sure that an alternate ruling is ‘not just a conclu‐
sory comment tossed in for good measure,’ but rather re‐
flected a ‘detailed explanation of the basis for the parallel re‐
sult.’” Shaw, 957 F.3d at 740 (quoting United States v. Foster,
701 F.3d 1142, 1158 (7th Cir. 2012)).
8                                                   No. 19‐3517

   The necessary explanation is lacking here. Rather than
consider the penalties and then decide that the existing sen‐
tence was nevertheless the best one, the court treated the new
penalties as irrelevant. That is inconsistent with the statutory
command to consider motions under section 404 “as if” the
Fair Sentencing Act had applied at the time the original crime
was committed. First Step Act § 404(b).
    In any case, the district court’s exercise of its discretion
was unreasonable because it did not address Corner’s argu‐
ment that he deserved a reduced sentence in light of the goals
and policies of the First Step Act. In sticking with the original
terms of reimprisonment and supervised release, it cited only
the reasons it had given at the time it first selected them—be‐
fore the First Step Act became effective. The sentence was
based on parameters that no longer apply, but the district
court did not analyze whether that sentence was still appro‐
priate in light of the changed statutory penalties (and corre‐
sponding effects on the sentencing guidelines) as the First
Step Act requires. Such a barebones explanation amounts to
no exercise of discretion at all. And a district court’s non‐ex‐
ercise of discretion is itself an abuse of discretion. Dolin
v. GlaxoSmithKline LLC, 951 F.3d 882, 889 (7th Cir. 2020).
    Congress afforded district courts wide discretion in the
First Step Act context. But by not considering what reduced
penalties would now apply to Corner’s offense, the district
court fell short of the review envisioned by the Act. Corner
has finished serving his revocation sentence, but his appeal is
not moot because the court could still reduce his term of su‐
pervised release. See Mont v. United States, 139 S. Ct. 1826,
1834 (2019); United States v. Sutton, 962 F.3d 979, 982 (7th Cir.
No. 19‐3517                                           9

June 23, 2020). We therefore VACATE the district court’s
judgment and REMAND for further proceedings.
