with whom Circuit Judge ALARCON, joins, Dissenting:
This case is laden with terms intended to evoke an emotional response. Jail officials ^placed an “aggressive” homosexual, who is a “registrable sex offender,” in the same cell with a “young and tender” plaintiff. I agree with the majority that a pretrial detainee must show conduct amounting to deliberate indifference to pursue a section 1983 action. To apply this standard, however, we need to look beyond the labels and examine the evidence.
The evidence presented by Redman does not approach the requisite level of culpability adopted by this court today. There has been no showing that the County or the individual defendants acted with deliberate indifference to Redman’s right to personal security. Further, Redman failed to present evidence that his injuries were *1450caused by action taken pursuant to a “policy” or “custom” promulgated by the County of San Diego (“County”) or any particular policymaker. In fact, the evidence shows that jail officials acted in contravention of the County’s policy regarding inmate segregation and placements. Although jail officials may have erred by assigning Redman to Clark’s cell, they were not acting pursuant to an official policy or custom or with deliberate indifference to Redman’s right to personal security. Accordingly, I respectfully dissent from the majority’s reversal of the directed verdict.
A. Requisite Level of Culpability
I agree with the majority that deliberate indifference is the level of culpability required to show that a pretrial detainee has been deprived of his or her right to personal security under the fourteenth amendment. The contours of this level of culpability, however, need clarification.
In adopting the standard of deliberate indifference, this court does not engage in a matter of mere semantics. Requiring deliberate indifference recognizes the high degree of deference owed by the courts to the informed decisions of prison officials. This standard acknowledges that prison officials, rather than the courts, are the individuals charged with making complex decisions involving a host of competing considerations, and are better capable of making these decisions. In examining the evidence, we must keep in mind:
[CJourts should defer to the informed discretion of prison administrators because the realities of running a corrections institution are complex and difficult, courts are ill equipped to deal with these problems, and the management of these facilities is confided to the Executive and Legislative Branches, not the Judicial Branch.
Bell v. Wolfish, 441 U.S. 520, 547 n. 29, 99 S.Ct. 1861, 1878 n. 29, 60 L.Ed.2d 447 (1979).
Although deliberate indifference does not require an intent to deprive an individual of his or her rights, or a “knowing willingness” that such consequences will occur, Whitley v. Albers, 475 U.S. 312, 321, 106 S.Ct. 1078, 1085, 89 L.Ed.2d 251 (1986), the standard does require a greater degree of culpability than negligence or gross negligence. To act in deliberate indifference to another’s rights, a defendant must have an awareness of a high probability of harm, and yet, consciously choose to disregard the risk. See Walker v. Norris, 917 F.2d 1449, 1454 (6th Cir.1990) (actor exhibits deliberate indifference by deliberately disregarding risk after becoming aware of risk). Because a defendant will rarely admit an awareness and conscious disregard of a risk, the trier of fact must examine objective criteria. W. Keeton, Prosser and Keeton on Torts 213 (5th ed.1984); Cortes-Quinones v. Jimenez-Nettleship, 842 F.2d 556, 558 (1st Cir.) (infer actor’s knowledge of risk based on magnitude of risk), cert. denied, 488 U.S. 823, 109 S.Ct. 68, 102 L.Ed.2d 45 (1988). This requires an analysis of the surrounding circumstances, which include the context in which the defendant chooses a course of action and the obviousness of the risk resulting from the defendant’s conduct. I assume this method of proving deliberate indifference is what the majority refers to when stating reckless conduct is “equivalent to a deliberate choice.” See also Fargo v. City of San Juan Bautista, 857 F.2d 638, 642 n. 7 (9th Cir.1988) (trier of fact may infer conscious disregard from conduct).
Thus, to prove deliberate indifference, or a conscious decision to disregard another’s rights, the context must be examined. As we stated in Berg v. Kincheloe, 794 F.2d 457 (9th Cir.1986), in applying the standard of deliberate indifference, the trier of fact must
consider whether, in allegedly exposing the prisoner to danger, the defendant prison official(s) were guided by considerations of safety to other inmates.... More generally, the legal standard must not be applied to an idealized vision of prison life, but to the prison as it exists, and as prison official(s) are realistically capable of influencing.
Id. at 462.
An analysis of the context in which prison officials act requires the trier of fact to *1451recognize the turbulent environment of a prison. “ ‘Prisons by definition, are places of involuntary confinement of persons who have a demonstrated proclivity for antisocial, criminal, and often violent conduct.’ ” Id. at 461 (quoting Hudson v. Palmer, 468 U.S. 517, 526, 104 S.Ct. 3194, 3200, 82 L.Ed.2d 393 (1984)). Further, the “ ‘prison setting is, at best, tense. It is sometimes explosive, and always potentially dangerous.’ ” Id. (quoting Marchesani v. McCune, 531 F.2d 459, 462 (10th Cir.), cert. denied, 429 U.S. 846, 97 S.Ct. 127, 50 L.Ed.2d 117 (1976)); see also Toussaint v. McCarthy, 801 F.2d 1080, 1100 (9th Cir.1986) (in assigning inmates, officials must not only predict behavior of single inmate, but must predict behavior of entire prison population), cert. denied, 481 U.S. 1069, 107 S.Ct. 2462, 95 L.Ed.2d 871 (1987).
Further, by adopting the standard of deliberate indifference, rather than a lesser standard of culpability, we acknowledge the broad discretion afforded prison administrators. The trier of fact, therefore, is not to reweigh the considerations affecting a choice of conduct and substitute its judgment as to the appropriate balance. If the course of conduct is affected by valid justifications in light of a risk which is not so great that a different course of conduct is mandated, the trier of fact must defer to the actor’s choice of conduct. It is in this context that the evidence of the defendants’ culpability must be considered.
B. County Policy
As the Supreme Court has stated repeatedly, to impose liability on a local government, the act or omission causing the deprivation of a constitutional right must be pursuant to an official policy or custom. See, e.g., Monell v. Department of Social Servs., 436 U.S. 658, 694, 98 S.Ct. 2018, 2037-38, 56 L.Ed.2d 611 (1978). A County may be held liable under section 1983 “only where its policies are the ‘moving force [behind] the constitutional violation.’ ” City of Canton v. Harris, 489 U.S. 378, 389, 109 S.Ct. 1197, 1205, 103 L.Ed.2d 412 (1989) (quoting Polk County v. Dodson, 454 U.S. 312, 326, 102 S.Ct. 445, 454, 70 L.Ed.2d 509 (1981)). The Supreme Court has emphasized a County may not be held vicariously liable for the acts of its employees. See, e.g., Monell, 436 U.S. at 691, 98 S.Ct. at 2036.
The “official policy” requirement was intended to distinguish acts of the municipality from acts of employees of the municipality, and thereby make clear that municipal liability is limited to action for which the municipality is actually responsible.
Pembaur v. Cincinnati, 475 U.S. 469, 479-80, 106 S.Ct. 1292, 1298-99, 89 L.Ed.2d 452 (1986) (footnote omitted).
In reviewing allegations that a governmental policy or custom caused the violation of a plaintiff’s constitutional rights, we must carefully examine the evidence to ensure vicarious liability is not imposed. See City of Oklahoma v. Tuttle, 471 U.S. 808, 823-24, 105 S.Ct. 2427, 2436-37, 85 L.Ed.2d 791 (1985). A policy may be shown “where — and only where — a deliberate choice to follow a course of action is made from among various alternatives” by policymakers. Meehan v. County of Los Angeles, 856 F.2d 102, 107 (9th Cir.1988) (quoting Pembaur, 475 U.S. at 483-84, 106 S.Ct. at 1300). Of course, “bald allegations” of a policy or custom are not sufficient, Polk, 454 U.S. at 326, 102 S.Ct. at 454, and evidence of more than a “nebulous” policy or custom is required. Tuttle, 471 U.S. at 823, 105 S.Ct. at 2436. Without such evidence, the plaintiff has failed to present a case for the jury. See id. at 823-24, 105 S.Ct. at 2436-37.
The majority holds either of two County policies or customs was the “moving force” behind the deprivation of Redman’s right to personal security. Neither of these purported “policies” was established by the evidence.
First, according to the majority, the County adopted a policy or custom of placing aggressive homosexuals in the mainline or general jail population, on the assumption that heterosexual inmates could protect themselves from homosexual assaults. The evidence showed, however, that the County had a written policy of segregating *1452aggressive homosexuals into isolation or special housing, and jail officials were aware of this requirement. Reporter’s Transcript, Vol. II, at 171, 235-36.1 Due to a lack of special housing, officials at the South Bay Detention Facility (“SBDF”) could not segregate the homosexuals. Id. at 171-72. Special rooms designed to house a single, troublesome prisoner were being used to house two prisoners. Id. Thus, although the County had a policy which required the segregation of aggressive homosexuals, in practice, officials at the SBDF did not follow this policy. In contravention of the County’s policy, officials put Clark in the jail’s general population, and Redman was assigned to his cell. Such conduct is insufficient for the imposition of Monell liability.
When an official’s discretionary decisions are constrained by policies not of that official’s making, those policies, rather than the subordinate’s departures from them, are the act of the municipality.
City of St. Louis v. Praprotnik, 485 U.S. 112, 127, 108 S.Ct. 915, 926, 99 L.Ed.2d 107 (1988).
Thus, contrary to the majority’s assertions, the County did not adopt a policy or custom of placing aggressive homosexuals into the general population of the jail. Nevertheless, the majority imposes liability upon the County based on Captain Beall’s assumption that heterosexuals in the general population can protect themselves from homosexuals who have been aggressive toward passive homosexuals in the homosexual module. Redman, however, failed to present evidence that Captain Beall possessed policymaking authority. An official’s acts may not be considered governmental policy unless “the official has been given ‘final authority to establish municipal policy with respect to the [challenged] action.’ ” Hammond v. County of Madera, 859 F.2d 797, 802 (9th Cir.1988) (quoting Pembaur, 475 U.S. at 481,106 S.Ct. at 1299). Captain Beall testified he operated under the direction of Sheriff Duffy and reported to an immediate superior, Inspector Powell. Id. The mere fact that Captain Beall could exercise discretion in executing the County’s policies and supervised the actions of deputies does not indicate he was a policymaker.
The fact that a particular official ... has discretion in the exercise of particular functions does not, without more, give rise to municipal liability based on an exercise of that discretion.
Collins v. City of San Diego, 841 F.2d 337, 341-42 (9th Cir.1988) (quoting Pembaur, 475 U.S. at 481-82, 106 S.Ct. at 1299). In sum, the evidence does not support the majority’s conclusion that the County adopted a policy or custom of placing aggressive homosexuals into the general population.
The majority then turns to overcrowding as a possible policy or custom. There was no evidence of the existence of such a County policy.
As discussed above, a “policy” is defined as a deliberate choice made by officials with final authority over the subject matter at issue. See also Pembaur, 475 U.S. at 481 n. 9, 106 S.Ct. at 1299 n. 9 (a “policy” is a “ ‘specific decision ... designed to carry out such a chosen course of action.’ ”) (quoting Webster’s Third New International Dictionary 1754 (1981)); Tuttle, 471 U.S. at 823, 105 S.Ct. at 2436 (the term “policy” “generally implies a course of action consciously chosen from among various alternatives”).
In City of Canton v. Harris, 489 U.S. 378, 390, 109 S.Ct. 1197, 1205-06, 103 *1453L.Ed.2d 412 (1989), the Supreme Court held inadequate training could represent a “policy” for which liability could be imposed upon a local government. To establish the existence of such a policy, the Court required proof of facts evidencing the local government’s awareness of a high probability of harm if the government failed to act.
[T]he need for more or different training [may be] so obvious, and the inadequacy so likely to result in the violation of constitutional rights, that the policymakers of the city can reasonably be said to have been deliberately indifferent to the need. In that event, the failure to provide proper training may fairly be said to represent a policy for which the city is responsible....
Id. (footnote omitted). Justice O’Connor clarified this requirement in her concurrence:
Where a § 1983 plaintiff can establish that the facts available to city policymakers put them on actual or constructive notice that the particular omission is substantially certain to result in the violation of the constitutional rights of their citizens, the dictates of Monell are satisfied. Only then can it be said that the municipality has made “ ‘a deliberate choice to follow a course of action ... from among various alternatives.’ ”
Id. at 396, 109 S.Ct. at 1208 (quoting Pembaur, 475 U.S. at 483, 106 S.Ct. at 1300) (emphasis added).
In the present case, Redman did not present any evidence that the County had actual or constructive notice that overcrowding presented a high probability of assault. To the contrary, as the majority acknowledges, Deputy Canfield testified he did not believe the SBDF was overcrowded. Reporter’s Transcript, Vol. II, at 235. More important, both Captain Beall and Deputy Green testified they were not aware of any sexual assaults at the SBDF prior to the assault at issue in this case. Reporter’s Transcript, Yols. I & II, at 113, 117, 211. From the record before us, it cannot be said the County was aware of a problem at the SBDF due to overcrowding and made a deliberate choice to ignore the problem or to refuse to take corrective action. Monell liability may not be imposed on the basis of this nonexistent policy-
Redman also failed to present evidence that the practice of placing aggressive homosexuals into the jail’s general population, or the practice of housing two persons in a cell designed to hold one person, was attributable to a decision made by any “policymaker.” As discussed above, there is no evidence that Captain Beall was a policymaker. There also is no evidence linking Sheriff Duffy to either of the purported County policies. The record is silent as to any role played by Sheriff Duffy other than the fact that he was the “head of the department.” Reporter’s Transcript, Vol. II, at 160.
In sum, there is no evidence of the existence of either County policy relied upon by the majority, nor is there any evidence that local practices at the SBDF were implemented by any policymaker. Thus, there is no basis for the imposition of liability against the County, or against any of the defendants, on the ground that a governmental policy caused the deprivation of Redman’s constitutional right to personal security.
C. County’s Culpability
Even assuming Redman introduced sufficient evidence that jail officials acted pursuant to relevant County policies, the evidence falls far short of establishing that these policies were applied with deliberate indifference to Redman’s right to personal security.
The policies identified by the majority focus on the placement of Clark in the general population and the assignment of Redman to Clark’s cell. The subsequent call from Mrs. Pearson, the mother of Red-man’s girlfriend, and the nature of the investigation by Deputy Green in response to the call are not relevant to these asserted policies. Deputy Green’s investigation may have been negligent, or perhaps more than negligent, but the majority makes no attempt to label Deputy Green a “policy*1454maker” or to attribute his investigation to a County policy.
The only evidence relied on by the majority to reach its conclusion that the County acted with deliberate indifference by placing Clark in the general population and by assigning Redman to Clark’s cell is Clark’s coercion of passive homosexuals while he was in the homosexual module. The evidence shows, however, that Clark did not misbehave while he was in the jail’s general population before he was transferred to the homosexual module or while he was in a low-security housing dorm after his transfer from the homosexual module. See Reporter’s Transcript, Vol. II, at 189-90. Contrary to the majority’s assumption, it was Clark who was at risk of being victimized in the general population by heterosexual inmates. While in the general population, the heterosexual inmates teased and sexually harassed Clark. Id. at 189. Clark’s parole officer requested Clark’s transfer to the homosexual unit because Clark had been the victim of harassment in the general population. Id. The evidence also shows that no sexual assaults had occurred at SBDF prior to the assault in this case. Reporter's Transcript, Vols. I & II, at 113, 117, 211. Further, there is no evidence that a homosexual who coerces “passive” homosexuals presents a threat to heterosexuals. This is simply an assumption inherent in the majority opinion without any support whatsoever in the evidence.
The majority also fails to consider the countervailing interests involved in placing an inmate such as Clark. Had officials not moved Clark out of the homosexual module, we would likely be addressing a section 1983 claim by an inmate victim assigned to the “passive” homosexual module. But the jail officials did move Clark. They moved him back into the general population where he had been the victim of harassment, but had never threatened a heterosexual. This involved a risk to Clark. It is not beyond peradventure that if Clark had been attacked, we would now be addressing a section 1983 claim by him. The point is that the placement of inmates within a jail is not an easy task and involves a number of competing concerns. Prison officials at the SBDF made a reasoned judgment where and with whom to house Clark based on information available to them. There is no evidence that the officials’ choice was unreasonable, much less deliberately indifferent. Given these circumstances, this court should not substitute its asserted omniscience for the reasoned choices made by the jail officials.
D. Individual Defendants’ Culpability
To impose liability under section 1983 on an individual defendant, the defendant’s act or omission must cause the deprivation of the plaintiff’s constitutional rights. The element of causation is “individualized and focus[es] on the duties and responsibilities of each individual defendant whose acts or omissions are alleged to have caused a constitutional deprivation.” Leer v. Murphy, 844 F.2d 628, 633 (9th Cir.1988). Further, the plaintiff “must establish individual fault ... as to each individual defendant’s deliberate indifference.” Id. at 634 (emphasis added).
When examining the liability of supervisors, “It is clear that the supervisors are not subject to vicarious liability, but are liable only for their own conduct.” Bergquist v. County of Cochise, 806 F.2d 1364, 1369 (9th Cir.1986); see also Hansen v. Black, 885 F.2d 642, 645 (9th Cir.1989) (“supervisory officials are not liable for actions of subordinates on any theory of vicarious liability”); Hunt v. Dental Dep’t, 865 F.2d 198, 200 (9th Cir.1989) (supervisor is not “vicariously liable for the fault of personnel” at the prison).
We have clarified the need for proof of a supervisor’s individual fault:
A supervisor may be liable if there exists either (1) his or her personal involvement in the constitutional deprivation, or (2) a sufficient causal connection between the supervisor’s wrongful conduct and the constitutional violation.
Hansen, 885 F.2d at 646 (emphasis added). The “sufficient causal connection” may be shown by evidence that the supervisor “implement[ed] a policy so deficient that the *1455policy ‘itself is a repudiation of constitutional rights...." Id. (quoting Thompkins v. Belt, 828 F.2d 298, 304 (5th Cir.1987)). However, an individual’s “general responsibility for supervising the operations of a prison is insufficient to establish personal involvement.” Ouzts v. Cummins, 825 F.2d 1276, 1277 (8th Cir.1987). The evidence of the individual defendants’ conduct must be examined in light of these principles.2
Redman failed to present any evidence of wrongful conduct by Sheriff Duffy. There is no evidence Sheriff Duffy was personally involved in the transfer of Clark to the jail’s general population or the assignment of Redman to a cell with Clark. There also is no evidence Sheriff Duffy implemented the policies identified by the majority. The only evidence concerning Sheriff Duffy’s responsibility for Redman’s injuries is testimony by Captain Beall that Sheriff Duffy was “the head of the department.” Reporter’s Transcript, Vol. II, at 160.
The majority bases Sheriff Duffy’s liability on his general supervisory responsibility over all county detention facilities. The majority concludes the jury could find Sheriff Duffy liable because there was evidence of “Sheriff Duffy’s ultimate direction of operations at the South Bay Detention Facility.” This evidence is not sufficient to show that Sheriff Duffy was personally involved in wrongful conduct, that he participated in implementing a deficient policy, or that his actions caused Redman’s injury.
In its attempt to avoid imputing the acts of subordinates to Sheriff Duffy to hold him vicariously liable, the majority relies on unsupported allegations in the complaint linking Sheriff Duffy to overcrowding of the jail. Contrary to these allegations, no evidence was produced at trial that Sheriff Duffy was responsible for, or even aware of, the alleged overcrowding at SBDF. The majority also cites with approval the portion of the complaint alleging Sheriff Duffy acted with deliberate indifference by “continupng] operations at [SBDF] despite such [overcrowding].... ” If this is true, to avoid liability, presumably sheriffs should “cease operations” at all jails which have an inmate population that exceeds design capacity; or perhaps they should arbitrarily release prisoners until the design capacity is not exceeded. Another option might be to transfer inmates to some undercrowded facility, but this presumes a fact not in evidence: that such a facility exists. These options, of course, are not viable. Yet by relying on “overcrowding,” the majority subjects Sheriff Duffy to liability without any showing that he knew about the alleged overcrowding or could have done anything about it if he did.
The majority apparently concludes Captain Beall is responsible for Redman’s injuries because he approved policies generated by the staff at the SBDF. See Reporter’s Transcript, Vol. II, at 175. The majority identifies the relevant policy as that of placing aggressive homosexuals into the general population. The majority first attributes this “policy” to the County even though the County had no such policy and despite the absence of any evidence that Captain Beall was a policy-maker. The majority then equates this “policy” with a practice at the SBDF for which it holds Captain Beall responsible.
Even assuming Captain Beall was responsible for this practice because he directed the placement of inmates at the SBDF, neither placing Clark into the jail’s general population nor placing Redman in Clark’s cell was deliberately indifferent to Redman’s interest in personal security. As discussed in preceding Section B, the jail officials did not act with deliberate indifference by placing Clark into the jail’s general population. The majority ignores the fact that there is no evidence Clark posed a threat to any heterosexual inmate while Clark was in the jail’s general population prior to his transfer to the homosexual module or while in a low-security housing dorm after his transfer from the homosexual module. Moreover, as previously stated, Captain Beall was not aware of any *1456sexual assaults at the SBDF prior to the assault in this case.
The majority also concludes a reasonable jury could find Captain Beall was deliberately indifferent because he was responsible for Redman’s placement into the general population. The majority opinion states Captain Beall “recogniz[ed] a particular risk to young inmates,” and ignored this risk by placing “young inmates” into the general population. The majority apparently believes Clark was a threat to Redman because Redman was classified as a “young and tender” inmate requiring special housing. There is no evidence, however, that Redman was ever classified as a “young and tender” inmate or any other type of inmate requiring special housing. Deputy Green and Captain Beall testified they did not believe Redman fit the classification of a “young and tender” inmate or any other type of inmate requiring special housing. Reporter’s Transcript, Vols. I & II, at 126, 208. Inmates not requiring special housing were placed into the general population. Id. at 176. Although Redman was initially housed in the young and tender module, pretrial detainees often were placed in that module so that jail officials could easily locate the detainees for transportation to court. Id. at 199, 202, 248.
CONCLUSION
There is no evidence in this case of the existence of any County policy which caused Redman’s injury. Nor is there any evidence that any defendant was a policymaker or was deliberately indifferent to Redman’s interest in personal security. Accordingly, the district court properly granted the defense motion for a directed verdict. I respectfully dissent from the majority opinion which holds to the contrary.
. The evidence indicating the County had a policy of segregating aggressive homosexuals includes testimony by Captain Richard Beall:
Q: Was there anything for a homosexual who was aggressive as far as his being housed separately?
A: We usually didn't know about that. If we knew about it and had strong reason to believe that he would attack other persons, then we would attempt to isolate him or keep in a small enough housing unit so he could be observed closer_
Reporter's Transcript, Vol. II, at 171. In addition, Deputy Gene Turner testified:
Q: You’re aware of the requirement that those who are individuals who are prone to assault staff or other inmates would be segregated; is that correct?
A: Yes, sir.
Id. at 235-36.
. Deputy Green’s conduct is not examined because he was never a defendant in the case; and, in any event, his conduct may not be imputed to any other defendant to establish liability under 42 U.S.C. § 1983. Bergquist, 806 F.2d at 1369.