Wisconsin inmate Reggie Townsend filed a civil-rights action under 42 U.S.C. § 1983 against Larry Fuchs, Security Director at the New Lisbon Correctional Institution, and Sergeant Jerry Alen, a correctional officer in the segregation unit at the prison. Townsend, who was held at New Lisbon at all times pertinent to this appeal, claimed that Fuchs violated his Fourteenth Amendment right to due process by placing him, for 59 days, in administrative segregation — or, as it is known within the Wisconsin Department of Corrections (WDOC), temporary lock-up (TLU). See Wis. Admin. Code DOC §§ 303.02(22), 303.11. Townsend also alleged that Alen deprived him of his Eighth Amendment right against cruel and unusual punishment by demonstrating deliberate indifference to the unsanitary conditions he endured while in TLU. Fuchs and Alen moved for summary judgment, but while their motion was pending, Townsend sought to amend his complaint to include New Lisbon Warden Catherine Farrey as a named defendant on both claims. The district court granted summary judgment for both Fuchs and Alen, and denied Townsend’s motion to amend. We affirm the district court’s grant of summary judgment for Fuchs and its denial of Townsend’s motion to amend. However, we reverse the court’s grant of summary judgment for Alen, and remand for further proceedings.
*767 I. History
Townsend’s civil-rights action has a convoluted factual and procedural history; we will endeavor to simplify the underlying proceedings, while simultaneously drawing all reasonable factual inferences in Townsend’s favor.
See Vinning-El v. Long,
According to the WDOC administrative code, TLU is a “nonpunitive segregated status allowing an inmate to be removed from the general population pending further administrative action.” Id. § 303.02(22). The “main purpose” of TLU is to detain an inmate temporarily “until it is possible to complete an investigation, cool down a volatile situation or hold a disciplinary healing.” Id. § 303.11 note. “The effort,” the code continues, “is to avoid punitive segregation without a prior hearing, while assuring that inmates can be separated from the general population when there is good reason to do so.” Id. For instance, prison officials may assign an inmate to TLU if the officials suspect that the inmate “may impede a pending investigation.” Id. § 303.11(4)(a). And in keeping with the “temporary” aspect of the assignment, there is a limit on the amount of time that an inmate may spend in TLU: the initial period of placement may not last longer than 21 days, and may be extended to a maximum of 63 days. See id. § 303.11(3).
Approximately 150 inmates were assigned to TLU at one time or another while prison officials attempted to determine who participated in the November 11 prison riot. Townsend himself was placed in TLU on November 15, after officials received word that, during the riot, he had destroyed evidence that could have revealed the identities of some of the inmates who were involved. See id. § 303.11(1), (4)(a). Upon his transfer, Townsend received two WDOC notice forms that provided the reason why he was placed in TLU: one explained that “the offender may impede a pending investigation,” and the other stated, “Pending Investigation of Staff Battery.” Townsend acknowledged those reasons by signing the notice forms.
Townsend remained in TLU for 59 days while prison officials investigated his role in the prison riot, and on January 13, 2005, he was transferred back to New Lisbon’s general population when the officials were unable to confirm that he had destroyed evidence regarding the riot. 1 In accordance with the WDOC administrative code, Townsend’s parole eligibility was not affected by his TLU placement, nor was his sentence extended because of it. See id. § 303.11 note. Townsend did not receive a conduct report, or was otherwise disciplined.
*768
That is not to say that Townsend’s experience in TLU was entirely pleasant; the accommodations afforded to him during his stay were less than hospitable. The cells in TLU are designed to house only one inmate at a time: each cell is 12 feet by 6$ feet; contains one bunk, one sink, and one toilet; and is “wet,” meaning that it features a shower that sprays onto the wall of the cell opposite the door and drains through the cell’s floor. But because of the inordinately large number of inmates placed in TLU on suspicion of participating in the prison riot, Warden Farrey authorized, and Sergeant Allen helped supervise, the “double-bunking” of inmates in TLU cells. Consequently, Townsend was placed in a cell that was already occupied, where he shared the sink, toilet, and shower. He was, however, given his own “bunk” — a thin mattress that was placed on the concrete floor adjacent to the shower, the only area in the cell where it would fit. We must assume, because the party resisting a motion for summary judgment receives the benefit of all reasonable inferences,
see Vinning-El,
In the weeks following his transfer back to New Lisbon’s general population, Townsend filed several complaints with the prison’s Inmate Complaint Examiner, challenging both his placement in TLU and the unsanitary conditions in his cell. After Townsend exhausted the administrative remedies available to him,
see
42 U.S.C. § 1997e(a); Wis. Admin. Code DOC § 310.05;
Dixon v. Page,
Townsend also alleged that Sergeant Allen deprived him of his Eighth Amendment rights by demonstrating deliberate indifference to his basic need for clean and sanitary bedding. According to Townsend, Allen knew that he was forced to sleep on a wet and moldy mattress, and yet did nothing to remedy the unsanitary conditions. After discovery commenced, Townsend submitted an affidavit and provided deposition testimony, in which he explained his allegations against Allen in greater detail. Specifically, Townsend stated that while he was in TLU, he personally complained about his mattress to Allen and requested a new, clean mattress for his cell. However, Townsend continued, Allen responded, “We can’t get you a mattress right now,” and denied his request without further explanation. Townsend further related that several prison guards later informed him that his request for a new mattress was denied because if he received the mattress, prison officials would have to provide a new mattress to everyone else in TLU. Townsend also stated that the unsanitary sleeping conditions caused him to suffer several severe ailments, such as respiratory problems, chest and stomach pains, and muscle aches.
Security Director Fuchs and Sergeant Allen disputed Townsend’s allegations and moved for summary judgment. Fuchs argued, among other things, that Townsend’s due-process claim was meritless because the conditions in TLU were not analogous to those conditions the Supreme Court deemed atypically and significantly harsh in Wilkinson. Allen, in turn, argued that Townsend’s Eighth Amendment claim failed because he was not personally responsible for the unsanitary condition of Townsend’s mattress. In support of his argument, Allen attested in an affidavit that Townsend never spoke with him regarding the condition of his mattress; as Allen put it, “[a]t- no time” did Townsend complain to him “about unsanitary or wet condition[s] of his cell or mattress,” nor did he “personally observe a problem concerning an unsanitary cell or wet mattress” in Townsend’s cell or any other cell in TLU. But in several proposed findings of fact that Allen later filed with the district court, he admitted that Townsend had complained to him about the state of his mattress and had requested a new one; Allen further stated that he did not provide Townsend with a new mattress, even though New Lisbon had clean mattresses available. Finally, Allen conceded that he understood that it is unhealthy to sleep on a wet and moldy mattress, and that people risk developing health problems if they are forced to sleep on such a mattress.
After briefing on the summary-judgment motion completed, Townsend sought leave to amend his complaint and add Warden Farrey as a defendant to both his due-process and Eighth Amendment claims. See Fed.R.Civ.P. 15(a). As Townsend alleged, Farrey visited the TLU unit during the time that he was assigned there and saw that, when inmates were double-celled, one inmate had to sleep on the cell floor. Townsend continued that Farrey was the “ultimate decision-maker” at New Lisbon during the 59 days he was confined in TLU, and accordingly was involved in denying him his due-process rights, and exhibited deliberate indifference to the unsanitary conditions he endured.
The district court granted Security Director Fuchs and Sergeant Allen’s motion for summary judgment. The court first rejected Townsend’s due-process claim against Fuchs on the ground that Townsend did not have a liberty interest in *770 avoiding TLU placement. The court likewise concluded that Townsend’s Eighth Amendment claim against Allen was merit-less. Although the court assumed that “being forced to sleep on a wet and moldy mattress for [59] days is sufficiently serious” to establish an Eighth Amendment violation, the court determined that Townsend failed to proffer any evidence showing that Allen was deliberately indifferent to the unsanitary conditions. As the court explained, Townsend “proposed no facts to show that he complained about his mattress to defendant Allen, that he asked defendant Allen for a replacement because his mattress was wet or foul smelling or that ... Allen was aware of the level of deterioration in the condition of plaintiffs mattress.”
Finally, the district court denied as futile Townsend’s motion to amend. Because Townsend had no liberty interest in avoiding placement in TLU, the court determined that he had no viable due-process claim against Warden Farrey. Likewise, the court continued, any Eighth Amendment claim against Farrey would fail because Townsend proffered no evidence showing that she was personally responsible for the conditions in his cell. The court accordingly entered judgment for Security Director Fuchs and Sergeant Allen, and closed the case.
II. Analysis
On appeal, Townsend attacks the district court’s grant of summary judgment for Security Director Fuchs and Sergeant Allen. Townsend also asserts that the court erred by denying his motion to amend his complaint. We will address these arguments in order, beginning with the district court’s grant of summary judgment.
A. The district court’s grant of summary judgment
By bringing his § 1983 action against Security Director Fuchs and Sergeant Allen, Townsend shouldered the burden of establishing that the men deprived him of his constitutional rights under the Fourteenth and Eighth Amendments, respectively.
See Johnson v. Snyder,
1. Townsend’s Fourteenth Amendment claim against Security Director Fuchs
We first address Townsend’s argument that the district court erroneously granted summary judgment for Security Director Fuchs. Townsend essentially reasserts the argument that he made before district court. Specifically, he contends that Fuchs violated his due-process rights under Sandin and Wilkinson by placing him in TLU without procedural protections.
Because it is undisputed that Townsend was not afforded a hearing or other procedural protections before he was placed in TLU, his argument turns on whether he had a constitutionally protected liberty interest in avoiding placement in TLU.
See Ky. Dep’t of Corrs. v. Thompson,
Here, it is clear that Townsend’s assignment to TLU was discretionary. In fact, by admitting that his placement in TLU was contingent upon prison officials’ continuing investigation into whether he destroyed evidence related to the prison riot, Townsend concedes that he was placed in TLU for discretionary reasons. See Wis. Admin. Code DOC § 303.11(1), (4)(a); see
also Lekas,
Townsend continues, however, that although he was placed in TLU for discretionary reasons, the conditions he endured while in TLU were sufficiently harsh to trigger the due-process protections announced in Sandin. Specifically, Townsend renews his contention that the conditions he faced in TLU — the double bunking, the sharing of the small wet cell and its amenities, and the limited human contact — were sufficiently analogous to the conditions of the state Supermax prison in Wilkinson to create a liberty interest in avoiding TLU.
Townsend misreads
Wilkinson,
and in so doing commits a mistake that renders inapt any comparison between the conditions in TLU and the conditions of the Supermax prison. As we noted in our recent decision
Gillis v. Litscher,
the Supreme Court in
Wilkinson
did not determine that the conditions in the Supermax prison created a liberty interest by themselves.
See Gillis,
This is not to say that Townsend has no avenue to seek redress for the conditions he experienced while in TLU. We conclude only that the conditions have no bearing on whether New Lisbon prison officials were required to provide Townsend with procedural protections before placing him in TLU. The issue of the cell conditions in TLU is best analyzed as a claim brought under the Eighth Amendment,
cf. Gillis,
2. Townsend’s Eighth Amendment claim against Sergeant Allen
Townsend next challenges the district court’s grant of summary judgment for Sergeant Allen. According to Townsend, he proffered evidence before the district court showing that Allen had actual knowledge that his health was jeopardized by sleeping on the wet and moldy mattress. That evidence, Townsend asserts, created a genuine issue of material fact as to whether Allen exhibited deliberate indifference to the unsanitary conditions in his cell.
*773
The Supreme Court has interpreted the Eighth Amendment as requiring a minimum standard for the treatment of inmates by prison officials: the prison conditions must not, among other things, involve “the wanton and unnecessary infliction of pain.”
Rhodes v. Chapman,
Based on the parties’ dearth of input on the matter, it appears that they assume that Townsend endured a prison condition sufficiently serious to constitute an Eighth Amendment violation. The parties’ assumption might be incorrect if Townsend himself contributed to the mattress’s foul state by, say, failing to place it on top of the bed while he or his cell-mate showered, and until the floor had dried.
See Freeman v. Berge,
*774
But that aside, we must assess the parties’ shared assumption against the record as it is currently developed. And, in that light, the parties’ assumption seems sound.
See McCord v. Maggio,
We therefore turn our attention to whether Townsend proffered evidence establishing that Sergeant Allen was deliberately indifferent to the unsanitary conditions in his cell. The district court concluded that Townsend proffered no such evidence; as the court explained, Townsend “proposed no facts” showing that he complained about his mattress to Allen. But the district court did not properly characterize the evidence when reaching this conclusion, and, more importantly, did not view the evidence in a light most favorable to Townsend.
See Vinning-El,
In other words, neither Townsend, nor Sergeant Allen, proffered evidence beyond their own testimony that either directly corroborated their respective stories, or completely refuted the competing version of events. Thus, the dispute over whether Allen knew about Townsend’s cell conditions comes down to a good old-fashioned swearing contest that can be resolved only by assessing the credibility of the two men. Credibility determinations, however, lie exclusively within the fact-finder’s domain and are not appropriate for a district court to make at the summary judgment stage,
see Anderson v. Liberty Lobby, Inc.,
Therefore, when we view the record in the light most favorable to Townsend, we see a material dispute over whether Sergeant Allen knew that Townsend was forced to sleep on the wet and moldy mattress while he was in TLU.
See Payne v. Pauley,
B. The district court’s denial of Townsend’s motion to amend
Finally, Townsend argues that the district court erred by denying his motion to amend his complaint and name Warden Farrey as a defendant. The district court concluded that such an amendment would be futile because Townsend’s proposed claims against Farrey would not survive summary judgment.
See King v. E. St. Louis Sch. Dist. 189,
496 F.3d
812,
819 (7th Cir.2007);
Sound of Music Co. v. Minn. Mining & Mfg. Co.,
III. CONCLUSION
To recap, we Affiem both the district court’s grant of summary judgment for Security Director Fuchs and its denial of Townsend’s motion to amend. However, we REVERSE the court’s grant of summary judgment for Sergeant Allen, and Remand for further proceedings.
Notes
. The parties inexplicably agree that Townsend was assigned to TLU for 63 days. We say ''inexplicably” because both sides also agree, and the record confirms, that Townsend was placed in TLU on Monday, Novem-her 15, 2004, and was transferred back to general population on Thursday, January 13, 2005. This period was 59 days, not 63. See http://www.timeanddate.com/date/duration. html.
