Opinion for the Court by Judge JON 0. NEWMAN, in which Chief Judge WINTER and Judges KEARSE, MINER, McLaughlin, leval, calabresi, and JOSÉ A. CABRANES join; opinion by Judge WALKER, in which Judge JACOBS joins, concurring in the judgment, but declining to reach the merits because of Teague v. Lane, 489 U.S. 288, 109 S.Ct. 1060, *64103 L.Ed.2d 334 (1989); dissenting opinion by Judge PARKER, in which Judges CARDAMONE and ALTIMARI join.
JON 0. NEWMAN, Circuit Judge:We granted rehearing in banc in three unrelated cases to consider issues concerning the lawfulness of the exclusion of the public from a criminal trial during the testimony of an undercover police officer. Each case presents primarily two specific issues: (1) whether the prosecution established a sufficient justification for courtroom closure to override the defendant’s usual right to a. public trial, and (2) whether a trial judge, acting upon a request for courtroom closure, is required to consider sua sponte alterna-' fives to closure during the testimony of one witness. These issues arise on appeals in three cases that considered petitions for ha-beas corpus filed by prisoners challenging state court convictions. In No. 95-2463, Steven Ayala appeals from the June 26, 1995, decision of the District Court for the Southern District of "New York (John F. Keenan, Judge) denying his petition. In No. 95-2626, Peter J. Lacy, Superintendent of Bare Hill Correctional Facility, appeals from the June 19, 1995, judgment of the District Court for the Southern District of New York (Shira Scheindlin, Judge) granting the petition of Charles Okonkwo. In No. 95-2801, Howard Pearson appeals from the October 26, 1995, judgment of the District Court for the Southern District of New York (Peter K. Leisure, Judge), denying his petition.
We conclude that in all three cases the prosecution sufficiently justified the courtroom closure, and that a trial judge, having already considered closure during the testimony of one witness as an alternative to complete closure, is not required to consider sua sponte further alternatives to closure but needs to consider only further alternatives suggested by the parties. We therefore affirm in No. 95-2463 (Ayala) and No. 95-2801 (Pearson) and reverse in No. 95-2626 (Ok-onkwo).
Background
All three petitioners were convicted in separate trials in New York Supreme Court of selling drugs; Their convictions were based on so-called “buy and bust” activities of undercover police officers. The officer, posing as a narcotics user, purchases the drugs, and the seller is arrested shortly thereafter. The details of the offenses are set forth in the panel opinions. See Ayala v. Speckard, 89 F.3d 91, 92 (2d Cir.) (“Ayala I”), modified on denial of rehearing, 102 F.3d 649 (2d Cir.1996) ("Ayala II”); Okonkwo v. Lacy, 104 F.3d 21, 22 (2d Cir.1997) (“Okonkwo ”); Pearson v. James, 105 F.3d 828, 829 (2d Cir.1997) (“Pearson ”). We detail separately the circumstances concerning the courtroom closure in each case.
In No. 95-2463 (Ayala), the State moved to close the courtroom to spectators during the testimony of Detective Willie Dotson, the undercover officer who purchased drugs from Ayala. At a hearing before the state court trial judge, Dotson testified that he had been making undercover drug purchases for two years and expected to continue doing so for approximately six months in the 41st Precinct of New York City, the precinct to which he was assigned. See Ayala I, 89 F.3d at 92-93. He also testified that he had been working in the specific area where Ayala’s sale occurred for the past month and knew that he would be returning there after his trial testimony. Transcript of State Court July 15, 1991, Hearing (“Ayala Transcript”) at 42. He identified that location as “the area around 1006 Intervale Avenue.” Id. at 46. Dotson asserted that if he was recognized by people in the courtroom and then returned to “this particular area,” he would “fear for [his] life.” Ayala I, 89 F.3d at 93. He also testified that, on prior occasions while he was working undercover, people on the street had indicated to others that he was a police officer. He also admitted that he testified about the need for courtroom closure in every case in which his purchases occasioned a trial. The trial judge credited Dotson’s testimony, Ayala Transcript at 50-52, and ordered the courtroom cleared of spectators during Dotson’s trial testimony. The judge made clear that he would be “troubled by the testimony of an officer who simply makes this application in every case regardless of any circumstances which applfy] specifically to the particular case in *65question,” id. at 50, and relied primarily on the fact that Officer Dotson would be returning to the precise location in which he had arrested the defendant, id. at 51.
In, No. 95-2626 (Okonkwo), the State moved at an in camera hearing to close the courtroom to spectators during the testimony of John Swift, the undercover officer who had purchased drugs from Okonkwo. He was a member of the Manhattan South Tactical Narcotics Team, with responsibility to investigate street sales of narcotics south of 59th Street in Manhattan. Swift testified that undercover officers follow the practice of “maintenance,” returning to the location where they had previously made drug purchases. Transcript of State Court February 5-6, 1990, Hearing (“Okonkwo Transcript”) at 4-5. He said that he expected to engage in “maintenance” in the area where he had purchased drugs from Okonkwo, id. at 7, which he described as “Cooper Square,” id. at 6.
Swift testified that, his life would be in danger if his identity as an undercover officer was “exposed to the community in the area where [he] would operate.” Okonkwo, 104 F.3d at 28. The trial judge found that Swift continues to work in the “general area” where the crime occurred, and that, if his identity became known, his life or at least his continuing undercover activity would be jeopardized. He therefore ordered the courtroom closed to spectators during Swift’s trial testimony. Okonkwo Transcript at 9.
In No. 95-2801 (Pearson), the State moved to close the courtroom to spectators during the trial testimony of Denise DiBenedetto, the undercover officer who purchased drugs from Pearson. Like the officer who purchased from Okonkwo, she was -assigned to the Manhattan South Tactical Narcotics Team. DiBenedetto testified that she had been working as an undercover officer for 15 months and was currently active in the area of “West 42nd Street and Eighth Avenue” in Manhattan. Transcript of State Court September 7, 1990, Hearing (“Pearson Transcript”) at 20. She said that she had been working in the described area 25 times in the past 30 days and was continuing to work there on ongoing investigations.
When asked what could happen if her identity was revealed to the public, she answered, “Okay my cover could be blown and I could get killed.” Pearson Transcript at 22. The trial judge found that DiBenedetto was still active in the area where she bought, drugs from Pearson and that she had reason to fear retaliation if her identity was disclosed. Responding to the defendant’s contention that courtroom closure during the testimony of undercover officers would be “automatic” if permitted in Pearson’s case, the trial judge disagreed, pointing out that in the last hearing he had held on a similar claim, he had denied closure. In Pearson’s case, the judge ordered the courtroom closed to spectators during DiBenedetto’s trial testimony.
Prior Proceedings
Ayala. Ayala’s conviction was affirmed, People v. Ayala, 202 A.D.2d 262, 608 N.Y.S.2d 642 (1st Dep’t 1994), and leave to appeal to the New York Court of Appeals was denied, People v. Ayala, 83 N.Y.2d 908, 614 N.Y.S.2d 390, 637 N.E.2d 281 (1994). His petition for a writ of habeas corpus to challenge his conviction on the ground of a denial of his constitutional right to a public trial was denied by Judge Keenan.
A panel of this Court, consisting of Judges Cardamone, Altimari, and Parker, reversed. Ayala I, 89 F.3d at 92. Writing for the panel, Judge Altimari relied on two grounds. First, he ruled that, although the State had an overriding interest in protecting both “the safety, as well as the confidentiality” of an undercover officer, the State had failed to show “a substantial probability” that this interest “would likely have been prejudiced” if the officer had testified in open court. Id. at 95. He pointed out that the officer had testified that there was nothing special about Ayala’s trial that made him fearful, and had not suggested that anyone in a position to “blow” his cover was likely to be in the courtroom when he testified. Id. The opinion appeared to rule that an inadequate showing of likely prejudice had been made with respect to the State’s interest in either the undercover officer’s “safety” or “cover.” Id.
*66Second, Judge Altimari ruled that a trial judge has an obligation sua sponte to consider alternatives to courtroom closure, and that the failure to do so in Ayala’s case was a further reason for ruling the closure to have violated the defendant’s right to a public trial. Id. at 96-97.
The State petitioned for panel rehearing, contending both that the panel’s rulings should be reconsidered and that the requirement of a trial judge’s sua sponte consideration of alternatives to closure was a “new rule” that could not be applied retroactively in a habeas petition in light of Teague v. Lane, 489 U.S. 288, 299-310, 109 S.Ct. 1060, 1069-93, 103 L.Ed.2d 334 (1989) (plurality opinion), and Penny v. Lynaugh, 492 U.S. 302, 313-14, 109 S.Ct. 2934, 2943-45, 106 L.Ed.2d 256 (1989) (adopting plurality opinion in Teague). In a per curiam opinion, the Ayala panel first rejected the Teague argument on the ground that the State had waived the argument by failing to assert it in opposition to Ayala’s appeal from the denial of his habeas petition. Ayala II, 102 F.3d at 651. The panel pointed out that Ayala’s appellate brief to the panel had urged both of the grounds on which the panel ultimately relied, thereby affording the State an opportunity to contend that agreement with either ground, especially the requirement of sua sponte consideration of alternatives, would be a new rule. Id.
Second, the panel ruled that, even if the Teague argument was not waived, no new rule had been announced since both grounds of the panel’s original opinion relied on “a straightforward application of the constitutional standards enunciated” in prior Supreme Court decisions. Id. at 652. However, with respect to the first ground— substantial probability of prejudice to an overriding state interest, the rehearing opinion distinguished between the State’s interest in the safety of the undercover officer and the State’s interest in- minimizing the risk of compromising the officer’s effectiveness. The panel restated its view that the State’s "showing was insufficient with respect to the safety interest, but asserted that the initial panel opinion “did not address” whether the State had made the requisite showing concerning compromising the officer’s effectiveness. Id. Finally, the rehearing panel restated its view that the trial judge must sua sponte consider alternatives to courtroom closure. Id. at 652-54. Ultimately, rehearing was denied solely for lack of sua sponte consideration of alternatives. Id. at 654.
Okonkwo. Okonkwo’s conviction was affirmed, People v. Okonkwo, 176 A.D.2d 163, 574 N.Y.S.2d 186 (1st Dep’t 1991), and leave to appeal to the New York Court of Appeals was denied, People v. Okonkwo, 79 N.Y.2d 862, 580 N.Y.S.2d 733, 588 N.E.2d 768 (1992). On his petition for a writ of habeas corpus to challenge his conviction on the ground of a denial of his constitutional right to a public trial, Judge Scheindlin concluded that the State had not shown an interest sufficient to warrant courtroom closure and that the state trial judge’s findings were insufficient for such closure. She ruled that the writ should issue unless the state trial court determined, upon adequate findings after an evidentiary hearing, that the closure was warranted. See Okonkwo, 104 F.3d at 22. She also ruled that the petitioner’s argument concerning lack of sua sponte consideration of alternatives had been procedurally defaulted for lack of explicit presentation to the state courts.
A panel of this Court, consisting of Judges Miner, Walker, and Leval, modified the District Court’s ruling and affirmed, as modified. The panel first ruled, in agreement with Ayala I, that the undercover officer’s “generalized concern for his safety” was insufficient to warrant closure. Okonkwo, 104 F.3d at 25. The panel next ruled that the District Court had failed to consider the State’s interest in maintaining the effectiveness of the undercover officer. The panel explicitly identified that interest as a sufficient state interest for purposes of courtroom closure, id., and appeared to agree with the state trial and appellate courts that substantial probability of prejudice to that interest had been shown, id. Finally, the panel ruled that Ok-onkwo’s argument concerning sua sponte consideration of alternatives had not been defaulted, and concluded, “constrained by Ayala,” id. at 26, that lack of such consider*67ation violated Okonkwo’s right to a public trial. The panel also ruled that the Ayala violation required the petitioner’s release in the absence of a retrial, rather than the renewed state court hearing that the District Court had ordered. Id.
Pearson. Pearson’s conviction was affirmed by the Appellate Division, People v. Pearson, 186 A.D.2d 61, 588 N.Y.S.2d 146 (1st Dep’t 1992), and by the Court of Appeals, People v. Martinez, 82 N.Y.2d 436, 604 N.Y.S.2d 932, 624 N.E.2d 1027 (1993). On his petition for a writ of habeas corpus to challenge his conviction on the ground of a denial of his constitutional right to a public trial, Judge Leisure concluded that the State had shown sufficient risk of prejudice to an overriding interest in the undercover officer’s safety and cover and that sua sponte consideration of alternatives was not required of the trial judge. He therefore denied the petition. See Pearson, 105 F.3d at 830.
A panel of this Court, consisting of Judges Newman, Jacobs, and Cabranes, reversed. Id. at 831. The opinion of themChief Judge Newman concluded that the State had “adequately supported an overriding interest in protecting the undercover officer from exposure of her identity.” Id. at 830. The opinion further ruled that the trial judge’s failure to consider alternatives sua sponte violated the requirement set forth in Ayala I and Ayala II, and therefore reversed the denial of habeas relief. Judges Jacobs and Ca-branes wrote a concurring opinion to express their disagreement with the Ayala requirement, though accepting its precedential force. Pearson, 105 F.3d at 831 (concurring opinion).
In banc rehearing. Rehearing in banc was sought and granted in Okonkwo and Pearson. Though our mandate had issued following the decision in Ayala II, we also voted to recall our mandate in that ease and rehear it along with Okonkwo and Pearson. We did so because rehearing of the latter two appeals would inevitably involve reconsideration of the rulings of the panel that decided Ayala I and Ayala II, and that panel included two senior judges who could participate in the in banc (even to a limited extent) only if it included rehearing of a decision by a panel of which they were members, see 28 U.S.C. § 46(c)(1). We invited and received supplemental briefs.
Discussion
I. The “New Rule” Issue
The State respondents raise an issue preliminary to our consideration of the merits of the -habeas petitions in all three cases. They contend that the petitioners are urging the application of a “new rule” within the meaning of Teague, 489 U.S. at 301, 315, 109 S.Ct. at 1070, 1077-78 (plurality opinion), which generally may not be applied retroactively in a habeas corpus proceeding to a state court conviction that has become final. See Penry, 492 U.S. at 313-14, 109 S.Ct. at 2943-45 (adopting the view of the Teague plurality opinion). Specifically, the respondents contend that we would be announcing a “new rule” if we accepted the petitioners’ claims that the prosecution had failed to demonstrate a sufficient state interest to warrant courtroom closure during the testimony of the undercover officers, and that the trial judges had erred by not considering alternatives to closure sua sponte.
In Teague, the Supreme Court was asked to apply to the petit jury the “fair cross section” requirement applicable to selection of a jury venire. See Taylor v. Louisiana, 419 U.S. 522, 95 S.Ct. 692, 42 L.Ed.2d 690 (1975). The Colirt ruled that before deciding the merits of that contention, it “should” ask whether such a rule would be applied retroactively; Teague, 489 U.S. at 300-01, 109 S.Ct. at 1069-70 (plurality opinion), a result that could occur only if the rule advocated by the habeas petitioner was “dictated by precedent existing at the time the defendant’s conviction became final,” id. at 301,109 S.Ct. at 1070 (emphasis in original), and, if not, whether either of two exceptions to the Teag-ue retroactivity principle applies, id. at 311, 109 S.Ct. at 1075 (exception for new rule that places primary conduct beyond proper lawmaking authority or requires observance of procedures implicit in concept of ordered liberty).
Where a court is asked to apply retroactively a rule announced prior to the filing of a *68habeas petition but after the petitioner’s conviction has become final, it will normally be obliged to make a Teague analysis and determine whether the rule sought to be applied is “new.” That w ,s the context in which the Supreme Court recently decided O’Dell v. Netherlands — U.S. -, 117 S.Ct. 1969, 138 L.Ed.2d 351 (1997). The Court had previously decided that a defendant facing the death penalty must be allowed to respond to a prosecutor’s claim of future dangerousness by informing the jury that he will not be eligible for parole. See Simmons v. South Carolina, 512 U.S. 154, 114 S.Ct. 2187, 129 L.Ed.2d 133 (1994). The habeas petitioner in O’Dell sought to have Simmons applied retroactively. Since the applicable rule had already been announced, the only issue was the rule’s retroactivity. See Butler v. McKellar, 494 U.S. 407, 415, 110 S.Ct. 1212, 1217-18, 108 L.Ed.2d 347 (1990) (determining that rule previously announced in Arizona v. Roberson, 486 U.S. 675, 108 S.Ct. 2093, 100 L.Ed.2d 704 (1988); concerning effect of request for counsel in separate investigation, was new); Penry, 492 U.S. at 319-28, 109 S.Ct. at 2947-52 (determining that rule previously announced in Eddings v. Oklahoma, 455 U.S. 104, 102 S.Ct. 869, 71 L.Ed.2d 1 (1982), and Lockett v. Ohio, 438 U.S. 586, 98 S.Ct. 2954, 57 L.Ed.2d 973 (1978), concerning consideration of mitigating circumstances in death penalty sentencing, was not. new). Our pending cases are proeedurally more like Teague itself, since petitioners ask us to announce rules that the respondents regard as “new” and at the same time to apply such rules to habeas corpus petitions. This procedural distinction between Teague and O’Dell does not lessen the significance of Teague; it simply creates for the habeas court an opportunity, absent in the O’Dell context, to determine whether special circumstances exist that make it appropriate to consider and reject a claim on the merits, rather than limiting consideration to whether the claim, if sustained, would constitute a new rule.
• In the special circumstances of these appeals, we do not believe that Teague precludes our consideration and rejection of the merits of the petitioners’ claims. See Collins v. Youngblood, 497 U.S. 37, 40-41, 110 S.Ct. 2715, 2718, 111 L.Ed.2d 30 (1990) (“Generally speaking, ‘[rjetroactivity is properly treated as a threshold question ....’”) (quoting Teague, 489 U.S. at 300, 109 S.Ct. at 1070 (emphasis added)). The Ayala panel has ruled that the state interests advanced to warrant closure during the testimony of an undercover officer were not sufficiently supported to warrant the closure that occurred and that a trial judge has an obligation sua sponte to consider alternatives even to closure during the testimony of one witness. If this in banc court were now to decide only that the rules announced in Ayala I and Ayala II are new, without deciding that they do not correctly interpret the Constitution, we would create considerable uncertainty for the district courts of this Circuit, and perhaps for the state courts as well. Though the in bane court could vacate the decisions of the Ayala panel, removing their prece-dential force, that course would leave uncertainty as to whether the decisions of that panel would again be made by the three judges of the Ayala panel in subsequent cases, and by other members of this Court. If that uncertainty can be dispelled by rejecting, not merely vacating, the decisions of the Ayala panel, district judges facing closure claims in the future will be usefully guided.
The present context also includes the unusual circumstance that the two principal issues raised in the three pending eases have both been recently decided by the New York Court of Appeals contrary to the decisions of the Ayala panel. See People v. Ramos, 90 N.Y.2d 490, 662 N.Y.S.2d 739, 685 N.E.2d 492 (1997). The interest in comity, which underlies Teague, 489 U.S. at 308, 109 S.Ct. at 1074, is plainly served by eliminating the tension between the panel’s rulings as to Ayala and the Court of Appeals’ rulings as to Ramos. Moreover, since our rulings on the merits leave the challenged convictions undisturbed, we do not impair the State’s interest in finality, which also underlies Teague, id. We therefore turn to the merits of these appeals.
II. The Applicable Standards for Courtroom Closure
The Sixth Amendment guarantees every person accused in a criminal proseeu*69tion the right to a “public” trial. U.S. Const. amend. 6. That basic right has a long and distinguished history. See In re Oliver, 333 U.S. 257, 266-73, 68 S.Ct. 499, 504-08, 92 L.Ed. 682 (1948). It applies not only to the evidence phase of a criminal trial, see Gannett Co. v. DePasquale, 443 U.S. 368, 379, 99 S.Ct. 2898, 2905, 61 L.Ed.2d 608 (1979), but also to other adversary proceedings, such as a pretrial suppression hearing, see Waller v. Georgia, 467 U.S. 39, 43, 104 S.Ct. 2210, 2213-14, 81 L.Ed.2d 31 (1984). The explicit Sixth Amendment right of the accused is complemented by an implicit, “qualified” First Amendment right of the press and the public of access to a criminal trial. See Press-Enterprise Co. v. Superior Court, 478 U.S. 1, 9, 106 S.Ct. 2735, 2740-41, 92 L.Ed.2d 1 (1986) (“Press-Enterprise II”) (access to transcript of preliminary hearing); Press-Enterprise Co. v. Superior Court, 464 U.S. 501, 104 S.Ct. 819, 78 L.Ed.2d 629 (1984) (“Press-Enterprise I ”) (access to jury selection); Globe Newspaper Co. v. Superior Court, 457 U.S. 596, 102 S.Ct. 2613, 73 L.Ed.2d 248 (1982) (access to trial and pretrial hearings); Richmond Newspapers, Inc. v. Virginia, 448 U.S. 555, 100 S.Ct. 2814, 65 L.Ed.2d 973 (1980) (access to trial).
However, closure of a criminal trial courtroom may constitutionally occur under limited circumstances. The strict standards for closure were first enunciated by the Supreme Court, with varying formulations, in cases considering the First Amendment access rights of the press and the public. Thus, in Richmond Newspapers, closure was permitted only upon a showing of “an overriding interest articulated in findings.” Id. at 581, 100 S.Ct. at 2829 (plurality opinion of Burger, C.J.). In Globe Newspaper, the Court said that closure to “inhibit the disclosure of sensitive information” required a showing that denial of public access “is necessitated by a compelling governmental interest, and is narrowly tailored to serve that interest.” 457 U.S. at 606-07, 102 S.Ct. at 2620. In Press-Enterprise //the Court said, “The presumption of openness may be overcome only by an overriding interest based on findings that closure is essential to preserve higher values and is narrowly tailored to serve that interest.” 464 U.S. at 510, 104 S.Ct. at 824.
These rigorous standards .were explicitly applied to limitations on a defendant’s Sixth Amendment right to a public trial in Waller, 467 U.S. at 47,104 S.Ct. at 2216 (“In sum, we hold that under the Sixth Amendment any closure of a suppression hearing over the objections of the accused must meet the tests set out in Press-Enterprise [I] and its predecessors.”). Waller reformulated the standards for courtroom closure into a four-factor test:
[1] the party seeking to close the hearing must advance an overriding interest that is likely to be prejudiced,
[2] the closure must be no broader than necessary to protect that interest,
[3] the tidal- court must consider reasonable alternatives to closing the proceeding, and
[4] it must make findings adequate to support the closure.
Id. at 48, 104 S.Ct. at 2216.
Shortly after Waller, in the context of closure of a preliminary hearing, ordered to avoid the adverse effects of pretrial publicity, the Court further refined the first factor to require “a substantial probability that the defendant’s right to a fair trial will be prejudiced by publicity that closure would prevent,” Press-Enterprise II, 478 U.S. at 14, 106 S.Ct. at 2743 (emphasis added), and repeated the third factor’s requirement of a finding demonstrating that “reasonable alternatives to closure cannot adequately protect the defendant’s fair trial rights,” id.
A. First Waller Factor — the Interest Justifying Closure.
As noted, the Supreme Court has used various formulations to describe the gravity of the interest that will justify courtroom closure, as well as the degree of certainty that the asserted interest will be harmed. The interest has been described as “overriding,” Waller, 467 U.S. at 48, 104 S.Ct. at 2216-17; Richmond Newspapers, 448 U.S. at 581, 100 S.Ct. at 2829-30, “compelling,” Globe Newspaper Co., 457 U.S. at 607, 102 S.Ct. at 2620, and “cause shown that outweighs the value of openness,” Press-Enterprise I, 464 U.S. at 509, 104 S.Ct. at 823. *70The Court has said that the asserted interest must be shown to be “likely to be prejudiced,” Waller, 467 U.S. at 48, 104 S.Ct. at 2216, and has more recently required “a substantial probability” that the interest will be prejudiced, Press-Enterprise II, 478 U.S. at 14, 106 S.Ct. at 2743.
Our Court has endeavored to reconcile the various formulations in the Supreme Court decisions by relating the gravity of the interest asserted to the degree of closure requested. Thus, in Woods v. Kuhlmann, 977 F.2d 74, 76 (2d Cir.1992), we ruled that only a “substantial reason” was required to justify exclusion from the courtroom of members of the defendant’s family during a witness’s testimony, after the witness reported that some of the family members had threatened her. See Guzman v. Scully, 80 F.3d 772, 775 (2d Cir.1996) (applying “substantial reason” standard for partial closure). Other circuits have taken the same approach. See United States v. Sherlock, 962 F.2d 1349, 1357 (9th Cir.1992) (as amended) (“substantial reason” for partial closure); Nieto v. Sullivan, 879 F.2d 743, 753 (10th Cir.1989) (same); Douglas v. Wainwright, 739 F.2d 531, 533 (11th Cir.1984) (same). “The burden on the movant [for closure] to show prejudice increases the more extensive the closure sought.” United States v. Doe, 63 F.3d 121, 129 (2d Cir.1995).
It may be doubted whether trial judges can make meaningful distinctions between “compelling” and “overriding” interests or can distinguish between whether such interests are “likely to be prejudiced” or whether there is a “substantial probability of’ prejudice. We believe the sensible course is for the trial judge to recognize that open trials are strongly favored, to require persuasive evidence of serious risk to an important interest in ordering any closure, and to realize that the more extensive is the closure requested, the greater must be the gravity of the required interest and the likelihood of risk to that interest. After all, a word like “overriding” is really not a calibrated measure of the gravity of an interest; it reflects a conclusion that a particular interest asserted, together with the likelihood of risk to that interest, is sufficient to justify the degree of closure sought.
B. Third Waller Factor — Consideration of ■ Alternatives.
The Ayala panel ruled that the third Waller factor, requiring consideration of reasonable alternatives to closure, imposed on a trial judge an obligation to consider alternatives sua sponte. In considering this issue, we gain some understanding of the Supreme Court’s requirement by first recalling that the Court said that the standards enunciated in prior First Amendment cases apply to the Sixth Amendment right at issue in Waller, and then by examining what the Court meant by “alternatives” in those First Amendment cases. In Press-Enterprise I, after noting that the trial judge had “closed an incredible six weeks of voir dire without considering alternatives to closure,” 464 U.S. at 513, 104 S.Ct. at 825, the Court suggested two possibilities: (1) “[t]hose parts of the transcript reasonably entitled to privacy could have been sealed without such a sweeping order,” id., and (2) the trial judge might have “disclose[d] the substance of the sensitive answers while preserving the anonymity of the jurors involved,” id. The import of the Court’s concern appears to be that the trial judge erred in not considering alternatives to complete closure. See id. (“[Tjhere was also a failure to consider alternatives to closure and to total suppression of the transcript.”). Similarly, in Press-Enterprise II, the Court faulted the California Supreme Court for its failure “to consider whether alternatives short of complete closure would have protected the interests of the accused.” 478 U.S. at 14, 106 S.Ct. at 2748 (emphasis added).
Some, but not all, members of the majority are of the view that Waller appears to indicate that alternatives to complete closure are what the Court required trial judges to consider sua sponte when First Amendment closure standards are applied in the Sixth Amendment context. After noting that the trial judge had not made findings to justify “closure of the entire hearing,” 467 U.S. at 48, 104 S.Ct. at 2216, the Court pointed out that the trial judge had not considered the alternatives of (1) “directing the government to provide more detail about its need for *71closure, in camera if necessary,” id., and (2) “closing only those parts of the hearing that jeopardized the interests advanced,” id. at 48-49, 104 S.Ct. at 2217.
Sincé none of the alternatives that the Supreme Court identified in Press-Enterprise I, Press-Enterprise II, or Waller had been suggested by any of the parties, it is arguable that the Court expects trial courts to consider lesser alternatives sua sponte only before taking the extreme step of closing an entire proceeding. That is the conclusion recently reached by the New York Court of Appeals. See Ramos, 90 N.Y.2d at 500-06, 662 N.Y.S.2d at 744-48, 685 N.E.2d at 497-501.
Moreover, even if the Supreme Court has imposed an obligation upon a trial judge to give sua sponte consideration to alternatives to complete courtroom closure, the Court has never held that a criminal case defendant who has not requested a more limited alternative has a right to a new trial, just because the trial judge failed to consider this or other alternatives sua sponte. The First Amendment cases did not require a new trial for any criminal defendant, and Waller, which ordered only the partial relief of a new suppression hearing, did so on review of the conviction of a defendant who had objected to the complete closure of the -hearing that had occurred in that case. Until the decision of the Ayala panel, no case of which we are aware had ever reversed a criminal conviction because the trial judge failed to consider an alternative to courtroom closure (whether complete or partial) that had not been requested by the defendant.1 There is certainly no automatic basis for doing so. Though the right of the public and the press to attend a criminal proceeding absent circumstances justifying closure is of undoubted importance, the reversal of a criminal conviction for a trial judge’s failure to consider an alternative not requested by a defendant is arguably too high a price to pay to protect that right.
In the pending eases, however, we need not decide whether a .sua sponte obligation to consider alternatives to complete closure exists because the trial judges in these cases took the far lesser step, of closing the courtroom only during the testimony of one witness, albeit an important one. Whether or not a sua sponte obligation exists to consider alternatives to complete closure, we see nothing in the First Amendment cases or in Waller to indicate that once a trial judge has determined that limited closure is warranted as an alternative to complete closure, the judge must sua sponte consider further alternatives to the alternative deemed appropriate. At that point, it becomes the obligation of the party objecting to the trial court’s proposal to urge consideration of any further alternatives that might avoid the need for even a limited closure. This too is the conclusion reached by the New York Court of Appeals. See Ramos, 90 N.Y.2d at 500-05, 662 N.Y.S.2d at 744-48, 685 N.E.2d at 497-501.
The pending cases well illustrate the hazard of obliging a trial judge, who has already considered the alternative of partial closure during-the testimony of one witness, to have a further obligation sua sponte to consider alternatives to the alternative. The petitioners suggest that among the further alternatives that the judge should have considered were disguising the undercover officer or placing a screen between the witness and the courtroom spectators. Yet refinements such as these encounter substantial objections. Disguising the witness risks lessening the jury’s opportunity to observe the witness’s demeanor and assess credibility, and a screen risks implying to the jury that the *72family or friends of the defendant in attendance are likely to be dangerous. Even if Waller requires a trial judge to consider alternatives to complete closure, we do not believe that the Supreme Court wanted trial judges selecting the alternative of limited closure to consider further alternatives that themselves pose substantial risks to a fair trial for the defendant. Of course, if some further alternative is suggested by the defendant or the prosecution, the trial judge should give it consideration.
IIL Application of Closure Standards to the Pending Cases
A. First Waller Factor. In each of the three pending cases, the state court trial judges adequately determined that courtroom closure was warranted during the testimony of the undercover officer. The officers in all three cases testified that they were continuing their undercover work and would soon be returning in an undercover capacity to the same areas where the defendants had been arrested. These areas were described with particularity — “the area around 1006 Intervale Avenue” (Ayala), “Cooper Square” 0Okonkwo), and “West 42nd Street and Eighth Avenue” (Pearson).
The state interest in maintaining the continued effectiveness of an undercover officer is an extremely substantial interest, and the trial judge in each case was amply justified in concluding that this interest would be seriously prejudiced by requiring the officer to testify in an open courtroom. There is no requirement that the prosecution must prove that particular individuals likely to attend the trial will disclose the officer’s identity. Of course, the defendant himself has an opportunity to observe the officer (a second opportunity, if the defendant is guilty), and might communicate a description of the officer to others, particularly if the defendant is at liberty pending trial. The defendant’s right of presence at his trial requires accepting that risk, but the right to a public trial does not require the further risk that the officer’s identity-will become known through observation by members of the public who might enter the courtroom and see the officer testifying. The gravity of the state interest in protecting the secrecy of the officer’s identity from casual observers and the likelihood that this interest will be prejudiced by the officer’s testifying in open court are both sufficiently substantial to justify the limited closure of the courtroom during the officer’s testimony. The closure is limited not only because it lasts only for the testimony of one witness, albeit an important witness, but also because there is no limitation at all on the right of the public or the press to examine the transcript of the officer’s testimony. Since the state interest in maintaining the secrecy of the undercover officer’s identity warranted the limited closure, we need not consider the respondents’ additional point that the closure was also justified by the risk to the officer’s safety.
B. Third Waller Factor. In all three cases, the trial judge closed the courtroom, with justification, only during the testimony of one witness, and did so without limiting access to the transcript of the officer’s testimony. No additional alternatives were suggested by any party, and the trial judges had no obligation to consider additional alternatives sua sponte. We note that none of the defendants requested that family members be permitted to remain in the courtroom, a request that would have required careful consideration by the trial judge. See Vidal v. Williams, 31 F.3d 67, 68-69 (2d Cir.1994) (writ of habeas corpus granted because of unwarranted exclusion of defendant’s family members); see also Guzman, 80 F.3d at 774-76 (writ of habeas corpus granted because, among other things, court failed to inquire into alleged exclusion of defendant’s family members).
C. Second and Fourth Waller Factors. There is no substantial issue raised as to the second and fourth factors. The limited closure occurring only during the testimony of the undercover officer was “no broader than necessary,” Waller, 467 U.S. at 48, 104 S.Ct. at 2216, to protect the interest in preserving the secrecy of the undercover officer’s identity, and the trial judges in each ease made findings “adequate to support the closure,” id.
*73Conclusion
For these reasons, in No. 95-2463 (Ayala) and No. 95-2801 (Pearson) we affirm the judgment of the District Court; in No. 95-2626 (Okonkwo) we reverse the judgment of the District Court and remand with directions to . enter judgment dismissing the petition. We also vacate the decisions in Ayala I and Ayala II.
. The dissent identifies two decisions granting habeas corpus relief in which a court’s failure to consider alternatives was included among the reasons for concluding that Waller's requirements had been violated. See 131 F.3d at 85, n. 12 (citing Davis v. Reynolds, 890 F.2d 1105 (10th Cir.1989), and Jones v. Henderson, 683 F.Supp. 917 (E.D.N.Y.1988)). 'Neither decision explicitly considers the issue of whether a trial judge’s consideration of alternatives to closure must be undertaken sua sponte, or the issue of whether lack of such sua sponte consideration requires reversal of a criminal conviction. Indeed, in Jones, the trial judge was faulted for closing the courtroom "without even affording defense counsel an opportunity to be heard,” id. at 923 (footnote omitted), properly indicating the need to hear from defense counsel before closure is ordered.