ESCHBACH, Circuit Judge.
The petitioner, an inmate in a federal penitentiary, filed this action for habeascorpus relief in federal district court challenging the constitutionality of an institution disciplinary hearing conducted in 1980 that resulted in the loss of his good-time credits. The district court concluded that the petitioner’s due-process rights had not been violated and granted summary judgment for the respondent.1 For the reasons stated below, we will affirm.
I
On November 20, 1979, Charles Hughes, an inmate at the United States Penitentiary in Lompoc, California, was stabbed to death in the prison. On November 21, 1979, the petitioner, Ruben Ramirez Sanchez, was placed in administrative segregation pending an investigation into Hughes’s death. On December 13, 1979, Sanchez received an incident report charging him with (1) “Killing” and (2) “Aiding Another and Making Plans to Commit” the killing.2 The incident report stated that “[cjonfidential information has named you as being one of the assailants in the stabbing death of inmate HUGHES, Chariest,] Reg[.] No. 68858-012(C)” that occurred in “C-Unit, Cell A-12” at “10:30 a.m.” on “November 20, 1979.”
On December 19, 1979, the Unit Disciplinary Committee (“UDC”) at Lompoc found Sanchez guilty of both offenses, and stated in its written decision that its findings were based on “[cjonfidential information obtained by institution staff, confidential memos and statement by reporting officers.” The UDC referred the matter to the Institution Disciplinary Committee (“IDC”) at Lompoc for a hearing. Sanchez was provided with notice that the IDC hearing was scheduled for December 27, 1979, and signed a form acknowledging that he had been informed of his rights.
On December 27,1979, Sanchez’s request for a two-week postponement was granted, and the IDC hearing was held on January 10, 1980. At the hearing, Sanchez denied that the incident report was “true as written” and maintained that he was in the C-Unit at the time of the murder, but on a different tier. Three inmates testified on behalf of Sanchez, and his remaining three witnesses were excused because Sanchez had indicated that their testimony would have been essentially the same as that of the first three. The IDC report includes a summary of the statements of the three inmates who testified. The IDC considered the testimony of the witnesses, as well as the “[cjonfidential memo from [Investigator Tom Lynch] identifying two inmate witnesses and their confidential information” in reaching its decision, and concluded that Sanchez’s “plans resulted in the death of inmate Charles HUGHES.” After finding [696]*696Sanchez guilty, the IDC ordered (1) a forfeiture of his statutory good time, (2) continued custody in administrative segregation, and (3) a disciplinary transfer.
Sanchez then filed an initial administrative appeal with the warden at Lompoc seeking restoration of his good-time credits and expungement of the incident report; relief was denied on January 25, 1980.3 He then appealed to the Regional Director of the Bureau of Prisons, who on March 12, 1980, found that the evidence before the IDC only supported the charge of aiding another and making plans to commit the murder, but not the murder charge. The Regional Director instructed the warden to correct any reports that indicated Sanchez had been found guilty of the actual killing. Further relief was denied. Sanchez attempted to file an appeal with the General Counsel, but it was untimely.
Sanchez was indicted by a grand jury and tried in 1982 in federal district court for the Central District of California for the murder of Hughes, conspiracy to commit murder, and aiding and abetting. The jury returned a verdict of not guilty. Sanchez then filed another series of administrative appeals relating to the 1980 IDC action. These appeals were rejected as untimely.4
Sanchez was later incarcerated at the United States Penitentiary at Marion, Illinois, and filed this action in the federal district court for the Southern District of Illinois on January 9, 1984. He sought federal habeas-corpus relief on the ground that he was denied due process at the 1980 IDC hearing at Lompoc.5 By consent of the parties, the case was submitted to a magistrate pursuant to 28 U.S.C. § 636(c). The warden transmitted to the court under seal the documents relied upon by the IDC (including the investigator’s memoranda). Each party moved for summary judgment. The magistrate granted the warden’s motion and denied that of Sanchez, and the petition for a writ of habeas corpus was accordingly denied. This appeal followed.
II
A. Failure to Exhaust Administrative Remedies
It is beyond dispute that Sanchez failed to exhaust his administrative remedies. The respondent brought this issue to the attention of the district court in its first motion for summary judgment, and filed two affidavits that documented the administrative appeals Sanchez had filed. Sanchez did not deny that he failed to meet the exhaustion requirement. After counsel was appointed to represent Sanchez, the original habeas petition was amended to include additional due-process claims. The respondent supplemented his motion for summary judgment to address these new allegations. The magistrate decided the case on the merits and did not discuss the exhaustion issue. The respondent now urges that the judgment below may be affirmed on the ground that Sanchez did not exhaust his administrative remedies. It is, of course, proper for the party in whose favor the judgment was entered to [697]*697assert any ground appearing in the record in support of the judgment, whether or not that ground was relied upon by the trial court. Whitley v. Albers, — U.S. -, -, 106 S.Ct. 1078, 1088, 89 L.Ed.2d 251 (1986); Farmer v. Prast, 721 F.2d 602, 606 n. 7 (7th Cir.1983).6
Federal prisoners are ordinarily required to exhaust administrative remedies before petitioning for a writ of habeas corpus. Jackson v. Carlson, 707 F.2d 943, 949 (7th Cir.), cert. denied, 464 U.S. 861, 104 S.Ct. 189, 78 L.Ed.2d 167 (1983); see also Anderson v. Miller, 772 F.2d 375, 377 (7th Cir.1985), cert. denied, — U.S.-, 106 S.Ct. 1210, 89 L.Ed.2d 322 (1986); Brice v. Day, 604 F.2d 664 (10th Cir.1979), cert. denied, 444 U.S. 1086, 100 S.Ct. 1045, 62 L.Ed.2d 772 (1980); Guida v. Nelson, 603 F.2d 261 (2d Cir.1979); United States ex rel. Sanders v. Arnold, 535 F.2d 848 (3d Cir.1976); Hardwick v. Ault, 517 F.2d 295 (5th Cir.1975); Willis v. Ciccone, 506 F.2d 1011 (8th Cir.1974). Because the time limits for the administrative appeals have long since elapsed and because the Bureau of Prisons has in no way indicated that it will waive the applicable time limits for those appeals, cf. Anderson, 772 F.2d at 378, Sanchez cannot now complete the process. His failure to pursue his administrative remedies to their conclusion constitutes a procedural default. Cf. Engle v. Isaac, 456 U.S. 107, 124-25 & n. 28, 102 S.Ct. 1558, 1570 & n. 28, 71 L.Ed.2d 783 (1982); Nutall v. Greer, 764 F.2d 462, 464 (7th Cir.1985).
The question presented under these facts is what should be the effect of such a default. The respondent urges that the appeal should be dismissed. We disagree, and find instead that Sanchez should be required to make a showing of “cause and prejudice.” This court adumbrated such a requirement in Anderson, 772 F.2d at 378. However, the issue was apparently not properly presented in that appeal, and we ruled that the prisoners had deliberately failed to comply with the established procedures for prosecuting appeals before the Bureau of Prisons, even though they had twice been warned of the inadequacies of their submissions. Id.
The cause-and-prejudice rule was originally articulated in Davis v. United States, 411 U.S. 233, 93 S.Ct. 1577, 36 L.Ed.2d 216 (1973). Davis involved a federal prisoner who, petitioning under 28 U.S.C. § 2255, sought to challenge for the first time the composition of the grand jury that had indicted him. The government argued that such a challenge was barred because the prisoner failed to comply with Fed.R. Crim.P. 12, which provides that objections to grand-jury composition be presented at trial, and that failure to do so constitutes a waiver of the objection, but that the court “for cause shown may grant relief from the waiver.” The Supreme Court concluded that review of the claim on a petition for habeas should be barred in the absence of a showing by the prisoner of cause for the failure to comply with procedural requirements and of actual prejudice resulting from the alleged constitutional violation. 411 U.S. at 243-45, 93 S.Ct. at 1583-84.
In Francis v. Henderson, 425 U.S. 536, 96 S.Ct. 1708, 48 L.Ed.2d 149 (1976), the Court applied the rule of Davis to a case involving a state procedural requirement that a challenge to the composition of the grand jury be raised before trial. The Court noted that the federal judiciary had the power to entertain such a challenge, but rested its holding on “considerations of comity and concerns for the orderly administration of criminal justice.” Id. at 538-39, 96 S.Ct. at 1710. Although the state rule at issue in Francis did not allow for an exception upon a showing of cause, the Court concluded that the cause-and-prejudice standard of Davis should nonetheless apply, because there was no reason to give greater preclusive effect to procedural defaults by federal prisoners than to similar defaults by state prisoners. Id. at 542, 96 S.Ct. at 1711. The rule of Francis was [698]*698extended in Wainwright v. Sykes, 433 U.S. 72, 97 S.Ct. 2497, 53 L.Ed.2d 594 (1977), in which the Court held that federal habeas review was barred, absent a showing of cause and prejudice, when the prisoner waived, under state law, his objection to the admission of his confession at trial. See also Engle v. Isaac, 456 U.S. 107, 129, 102 S.Ct. 1558, 1572-73, 71 L.Ed.2d 783 (1982). In United States v. Frady, 456 U.S. 152, 167-68, 102 S.Ct. 1584, 1594, 71 L.Ed.2d 816 (1982), the Court applied a requirement of cause and prejudice in a § 2255 action involving Fed.R.Crim.P. 30, which, unlike Rule 12, contained no explicit exception to the requirement of a timely challenge to jury instructions. See also Nutall v. Greer, 764 F.2d 462 (7th Cir.1985) (state prisoner who fails to seek leave to present to highest state court constitutional objections forming basis of his habeas petition waives those objections unless he can show cause and prejudice); Norris v. United States, 687 F.2d 899 (7th Cir.1982) (cause-and-prejudice standard applicable in determining whether constitutional issue not raised on direct appeal from conviction could be considered in § 2255 proceeding).
As the discussion above indicates, the cause-and-prejudice requirement is generally applied to resurrect a federal habeas petition otherwise precluded by a procedural default, whether the default occurs in federal or state court, at trial or on appeal, and whether or not the procédural rule expressly incorporates a cause-and-prejudice standard.7 Although courts in cases involving state prisoners usually cite comity as the reason for the cause-and-prejudice requirement, see Wainwright, 433 U.S. at 84, 97 S.Ct. at 2505, that rationale does not, of course, support its application to those convicted in federal courts. See Frady, 456 U.S. at 162-66, 102 S.Ct. at 1591-93. Rather, the underlying policy seems to be that, before either a state or federal prisoner may seek federal habeas relief, he must first present his claim to the forum initially available, primarily because of the costs associated with granting a writ of habeas corpus. See Engle, 456 U.S. at 126-29, 102 S.Ct. at 1571-72 (discussion of costs). The forum with the primary jurisdiction does not simply provide a preliminary determination, but a final one, and the grant of a habeas writ is intended to be the exception, not the rule. For state prisoners challenging their convictions, that initial forum is the state court system. For federal prisoners challenging their convictions, it is the federal courts in the direct appeal process. For federal prisoners challenging disciplinary proceedings, it is the administrative process. It would be anomalous to allow prisoners challenging their convictions to overcome the bar of a procedural default in the court system through a showing of cause and prejudice, but to dismiss outright the claims of the same prisoners challenging prison disciplinary actions because of a procedural default in the administrative process. Cf. Francis, 425 U.S. at 542, 96 S.Ct. at 1711.
In addition, the reasons for requiring that prisoners challenging disciplinary actions exhaust their administrative remedies are analogous to the reasons for requiring that they exhaust their judicial remedies before challenging their convictions; thus, the effect of a failure to exhaust in either context should be similar. As the Supreme Court noted in Schlesinger v. Councilman, 420 U.S. 738, 756-57, 95 S.Ct. 1300, 1312, 43 L.Ed.2d 591 (1975):
The [exhaustion] rule, looking to the special competence of agencies in which Congress has reposed the duty to perform particular tasks, is based on the need to allow agencies to develop the facts, to apply the law in which they are peculiarly expert, and to correct their own errors. The rule ensures that whatever judicial review is available will be informed and narrowed by the agencies’ own decisions. It also avoids duplicative proceedings, and often the agency’s ulti[699]*699mate decisions will obviate the need for judicial intervention.
We also observe that circumvention of the administrative process diminishes the effectiveness of the agency by encouraging prisoners to ignore its procedures. See McKart v. United, States, 395 U.S. 185, 195, 89 S.Ct. 1657, 1663, 23 L.Ed.2d 194 (1969); see also Brice, 604 F.2d at 666-68; Smith v. Fenton, 424 F.Supp. 792, 795-99 (E.D.Ill.1976).
Thus, we reaffirm that a federal prisoner challenging a disciplinary decision within the federal institution must exhaust his administrative remedies before seeking federal habeas relief. In addition, we hold that, if the prisoner has failed to exhaust and the administrative process is now unavailable, his habeas claim is barred unless he can demonstrate cause and prejudice. As noted above, the district court did not rule on the exhaustion question. We could remand for further proceedings, but, as the discussion in the following section will indicate, a remand is unnecessary, because Sanchez cannot demonstrate prejudice. See Nutall, 764 F.2d at 465.
B. Prejudice
1. Use of Confidential Information
Sanchez’s primary claim on appeal is that he was denied due process of law at the 1980 IDC hearing that led to his adjudication of guilt and the loss of his good-time credits. He specifically alleges that the hearing was constitutionally infirm because the IDC did not determine that the confidential informants were reliable and because a showing was not made that the informants were in fact reliable. Sanchez rests his claim on the decision of the Supreme Court in Wolff v. McDonnell, 418 U.S. 539, 94 S.Ct. 2963, 41 L.Ed.2d 935 (1974) and this court’s decision in McCollum v. Miller, 695 F.2d 1044 (7th Cir.1982).
In Wolff, the Supreme Court set forth the due-process requirements for prison disciplinary proceedings. The Court noted that, although a prisoner is not wholly stripped of constitutional protections when he is imprisoned, lawful imprisonment necessarily makes unavailable many rights and privileges of the ordinary citizen.8 In addition, the Court noted that disciplinary proceedings are not part of a criminal prosecution and, therefore, that the full panoply of rights due a defendant in criminal cases does not apply. Although prisoners may have a liberty interest in good-time credits, there must be a mutual accommodation between (1) the needs and objectives of the correctional institution and (2) the provisions of the Constitution that are of general application. Id., 418 U.S. at 555-57, 94 S.Ct. at 2974-75.
The Court in Wolff looked to the procedures developed in the context of revocation of parole and probation,9 and concluded that some, but not all, of these procedures should apply to disciplinary proceedings implicating a constitutionally protected interest. After noting that parole and probation revocation and prison discipline implicate different interests and that the respective proceedings are conducted in different settings, id. at 558-63, 94 S.Ct. at 2976-78, the Court held that, in the context of disciplinary proceedings, prisoners were entitled to 24 hours’ advance written notice of the charges against them; the right to call witnesses and present documentary evidence in their defense, unless doing so would jeopardize institutional safety or correctional goals; the aid of a staff member or inmate in presenting'a defense, provided the accused inmate is illiterate or the issues complex; and an impartial tribunal. Id. at 563-72, 94 S.Ct. at 2978-82. The Court also concluded that there must be a “written statement by the factfinders as to the evidence relied on and reasons for the disciplinary action.” Id. at 563-72, 94 S.Ct. at 2978-82. The Court stated that “[wjithin the limits set forth in this opinion we are content for now to leave the continuing [700]*700development of measures to review adverse actions affecting inmates to the sound discretion of corrections officials administering the scope of such inquiries.” Id. at 568, 94 S.Ct. at 2981.
At issue in McCollum v. Miller, 695 F.2d 1044 (7th Cir.1982), were the due-process requirements for disciplinary proceedings where the evidence in support of a finding of guilt was provided by confidential informants. Wolff requires written notice of the disciplinary charge sufficient to mount a defense. The general notice the prisoner in McCollum received of the charges against him precluded the preparation of an effective defense. More detailed notice could not be given, however, without revealing the identities of the informants. In addition, the investigator did not give his report under oath, and he did not testify at the hearing. The IDC would not vouch for the credibility of the informants, but did indicate that the use of informants had proved reliable in the past, although it was apparently not referring to the specific informants involved. This court found that, because there was a significant risk of error under these facts, these procedures did not comport with due process, but concluded that the record was not sufficiently developed to permit a determination of what “additional safeguards” were appropriate in light of Wolff. We noted that it should be “feasible to insist that the [IDC] require that its investigative reports be under oath and that the investigator appear in person and be available for cross-examination; but we are not sure whether it is feasible to go further and require the [IDC] to interview — in camera, of course — some or all of the informants.”10 This court did not explicitly hold that the IDC must make a reliability finding in all disciplinary proceedings.
Confidential informants were again at issue in Jackson v. Carlson, 707 F.2d 943 (7th Cir.), cert. denied, 464 U.S. 861, 104 S.Ct. 189, 78 L.Ed.2d 167 (1983), a consolidated appeal of the habeas claims of five federal prisoners. The IDC found one of the prisoners guilty on the basis of an unsworn investigator’s report, and the charge was supported by evidence from informants and a prison employee. The investigator did not testify, and the prisoner was not given the report or the names of the informants. He was, however, given detailed notice of the charges against him. His hearing was held to comport with due process. Id. at 948. Another prisoner was found guilty on the basis of confidential information, but had adequate notice of the incident, which should have allowed him to identify the informants. In addition, the chairman of the IDC stated on the record that he had firsthand knowledge of the informants and considered them reliable because of “their past record of reliability.” These proceedings were also considered constitutional. Id. This court in Jackson did not read McCollum to require an express reliability finding from the IDC in every case. Id. at 947, 948.
In Dawson v. Smith, 719 F.2d 896, 899 (7th Cir.1983), cert. denied, 466 U.S. 929, 104 S.Ct. 1714, 80 L.Ed.2d 186 (1984), however, McCollum was apparently interpreted to require a reliability finding whenever information relied upon by the IDC was obtained from confidential informants. In that case, the investigator’s report stated that the confidential source was considered reliable, and it appeared that the IDC adopted the credibility determination of the investigator. Thus, due process had been observed. 719 F.2d at 899. In Mendoza v. Miller, 779 F.2d 1287,1293 (7th Cir.1985), it was stated that “[t]o protect the inmate’s interest in a fair hearing, our court requires some indication of the reliability of confidential informants when confidential information is the basis for a prison disciplinary decision.” McCollum was read to require that information “supplied by prison informants must be supported by some indication of reliability.” 779 F.2d at 1295.
[701]*701As the discussion above indicates, McCollum addressed the risk of error in (thus, in a general sense, the reliability of) the IDC’s use of confidential informants in a specific prison disciplinary proceeding. The aggravating factor, however, was the generality of the notice given the prisoner, which precluded the preparation of an adequate defense. This court concluded that under those facts, when the notice requirements of Wolff could not be met (a situation never addressed in Wolff itself), “additional safeguards” were necessary. In Dawson and Mendoza, however, we read McCollum more broadly and departed from a case-by-case analysis to set forth a general rule that no longer focused primarily of the type of notice that the prisoner received, but rather on the quality of the evidence upon which the IDC relied. It should be noted that, although in Anglo-American jurisprudence a tribunal is not ordinarily required to provide an assessment of the reliability of witnesses,11 the setting of disciplinary proceedings departs from the Anglo-American model of a judicial tribunal. See generally Cleavinger v. Saxner, — U.S. -, 106 S.Ct. 496, 502, 88 L.Ed.2d 507 (1985); Hewitt v. Helms, 459 U.S. 460, 472-75, 103 S.Ct. 864, 871-73, 74 L.Ed.2d 675 (1983); Wolff, 418 U.S. at 561-63, 568, 94 S.Ct. at 2977-78, 2980-81. Indicia of reliability provide additional protection when other rights of the accused have been circumscribed in the relatively informal setting of prison disciplinary proceedings.
2. Retroactivity
Even if we assume arguendo that Sanchez’s characterization of McCollum is correct, the rule would not necessarily apply in the instant case. As the Supreme Court stated in Wolff, 418 U.S. at 573-74, 94 S.Ct. at 2982-83:
The Court of Appeals held that due process requirements in prison disciplinary proceedings were to apply retroactively so as to require that prison records containing determinations of misconduct, not in accord with required procedures, be expunged. We disagree and reverse on this point.
The question of retroactivity of new procedural rules affecting inquiries into infractions of prison discipline is effectively foreclosed by this Court’s ruling in Morrissey that due process requirements there announced were to be “applicable to future revocations of parole,” 408 U.S., at 490, 92 S.Ct., at 2604 (emphasis supplied). Despite the fact that procedures are related to the integrity of the factfinding process, the context of disciplinary proceedings, where less is generally at stake for an individual than at a criminal trial, great weight should be given to the significant impact a retroactive ruling would have on the administration of all prisons in the country, and the reliance prison officials placed, in good faith, on prior law not requiring such procedures. During 1973, the Federal Government alone conducted 19,000 misconduct hearings, as compared with 1,173 parole revocation hearings, and 2,023 probation revocation hearings. If Morrissey-Scarpelli rules [dealing with parole and probation] are not retroactive out of consideration for the burden on federal and state officials, this case [involving the application of new procedural requirements in prison disciplinary hearings] is a fortiori. We also note that a contrary holding would be very troublesome for the parole system since performance in prison is often a relevant criterion for parole. On the whole, we do [702]*702not think that error was so pervasive in the system under the old procedures as to warrant this cost or result.
It is clear then that, as a general matter, new procedural rules for disciplinary proceedings will not be applied retroactively. Thus, the constitutionality of the IDC hearing must be considered under the law in existence at the date of the hearing. See Cox v. Cook, 420 U.S. 734, 95 S.Ct. 1237, 43 L.Ed.2d 587 (1975); Johnson v. Holley, 528 F.2d 116 (7th Cir.1975) (overruled in part on other grounds, see Bryant v. Grinner, 563 F.2d 871, 871-72 (7th Cir. 1977)); Thomas v. Pate, 516 F.2d 889 (7th Cir.), cert. denied, 423 U.S. 877, 96 S.Ct. 149, 46 L.Ed.2d 110 (1975); Edwards v. Illinois Department of Corrections, 514 F.2d 477 (7th Cir.1975); Chapman v. Kleindienst, 507 F.2d 1246 (7th Cir.1974). The IDC hearing for Sanchez was held on January 10, 1980. McCollum was decided on December 20, 1982. Assuming for the moment that McCollum prescribed a new procedural rule, it would appear that Sanchez could not rely on it, as his hearing antedated the decision. It is true that in subsequent cases McCollum was discussed in connection with IDC hearings conducted prior to December 20, 1982. See Mendoza, 779 F.2d at 1290 (IDC hearing held on April 3, 1981); Dawson, 719 F.2d at 897 (IDC hearing held on October 25, 1977); Jackson, 707 F.2d at 946 (docket numbers indicate federal appeals filed in 1981 and 1982). However, the propriety of the retroactive application of McCollum was not discussed in Mendoza, Dawson, and Jackson, and is therefore an open question in this circuit. Thus, we must determine whether McCollum set forth a new rule, which under Wolff can only have prospective application.
Sanchez argues that McCollum’s requirement of indicia of reliability was inherent in the holding in Wolff that there must be a “written statement by the fact-finders as to the evidence relied on and reasons for the disciplinary action.”12 We disagree. The McCollum rule is not inconsistent with Wolff, but neither is it compelled by the earlier decision.13 Wolff has not been read as holding that prisoners are generally entitled to due process in disciplinary proceedings. To the contrary, it sets forth specific minimum procedures and expressly leaves the development of additional safeguards to the discretion of the prison authorities. See, e.g., Edwards, 514 F.2d at 479. The Court was unwilling to go further, and has continued to read Wolff as calling for no more than the procedures specifically enumerated therein. See Superintendent v. Hill, — U.S. -, 105 S.Ct. 2768, 86 L.Ed.2d 356 (1985); Ponte v. Real, — U.S. -, 105 S.Ct. 2192, 85 L.Ed.2d 553 (1985). See also Mendoza, 779 F.2d at 1301 (Swygert, J., dissenting) (Wolff “simply did not address what other procedures were constitutionally necessary as a check on the use by prison officials of confidential, and perhaps unreliable, prison information”); Dawson, 719 F.2d at 889; Kyle v. Hanberry, 677 F.2d 1386, 1389 (11th Cir.1982) (Wolff does, not consider use of confidential informants).
The case law of this circuit makes clear that a decision calling for a specific procedural rule for disciplinary proceedings that goes beyond the constitutional mini[703]*703mums of Wolff will be given prospective effect only. See, e.g., Thomas, 516 F.2d at 890. The passage from Wolff quoted above illustrates that the primary question is whether the rule imposes greater burdens on the prison authorities, not whether it increases the accuracy of the proceedings. It is true that the Court in Wolff did not say that procedural changes could never be applied retroactively, but indicated that the procedural defects at issue did not so undermine the legitimacy of prior disciplinary hearings as to warrant imposing the burden of retroactivity on prison officials. If the sweeping changes mandated in Wolff to reduce the risk of inaccurate results are not to be applied retroactively, then the comparatively small change made in McCollum cannot, if it burdens prison officials. If McCollum is applied retroactively, then all disciplinary proceedings conducted since Wolff, i.e., June 1974, involving evidence from confidential sources are open to challenge. Tens of thousands of findings of guilt could be subject to invalidation. Such a result, with its highly disruptive effect on the disciplinary, parole, probation, and judicial processes, would be manifestly inconsistent with the ruling in Wolff. We, therefore, hold that the rule of McCollum cannot be applied to prison disciplinary proceedings held prior to the date of its decision, i.e., December 20, 1982.
As noted above, Sanchez’s due-process claim must be determined by the state of the law as it existed in January 1980, the date his IDC hearing was held. As we have concluded, Wolff did not mandate a reliability finding. Thus, Sanchez cannot rest on his citation to that decision. Because McCollum cannot be applied retroactively, his reliance on that decision is also unavailing. We cannot be unmindful that Sanchez was represented by counsel. The respondent raised the retroactivity issue below and on appeal. Sanchez did assert that McCollum or Wolff could be applied to his hearing, but elected not to argue in the alternative and, thus, did not discuss the state of the law in 1980.14 Rule 28 of the Fed.R.App.P. requires that the appellant present argument with citations to the relevant authorities. It is not the obligation of this court to research and construct the legal arguments open to parties, especially when they are represented by counsel. See May v. Evansville-Vanderburgh School Cory., 787 F.2d 1105, 1118 (7th Cir.1986); Libertyville Datsun Sales v. Nissan Motor Corp., 776 F.2d 735, 737 (7th Cir.1985). Sanchez, therefore, has waived the claim that his disciplinary hearing did not comport with the due process requirements existing in January 1980.15 Cf. Walton v. United Consumers Club, Inc., 786 F.2d 303, 315 (7th Cir.1986); Graczyk v. United Steelworkers of America, 763 F.2d 256, 261 n. 6 (7th Cir.), cert. denied, — U.S. -, 106 S.Ct. 335, 88 L.Ed.2d 319 (1985).
Ill
As developed in Section II, suyra, the law did not require that there be indications in the administrative record of the reliability of confidential informants when Sanchez’s disciplinary hearing was held in January 1980. He cannot, therefore, show [704]*704that he was prejudiced by the failure to exhaust his administrative remedies. The judgment of the district court is AFFIRMED.