Theresa K. GOODEN, Plaintiff-Appellee, v. HOWARD COUNTY, MARYLAND, c/o Elizabeth Bobo, County Executive; Nancy Yeager, individually and in her capacity as a police officer of the Howard County Police Department; Frank N. Salter, individually and in his capacity as a police officer of the Howard County Police Department; William J. Pollack, individually and in his capacity as a police officer of the Howard County Police Department, Defendants-Appellants, and Frederick W. Chaney, in his capacity as Chief of Police of the Howard County Police Department; Unknown and Unidentified Police Officers of the Howard County Police Department, hereinafter referred to as John Doe I, John Doe II, John Doe III, John Doe IV and John Doe V, who were present at and involved in the incidents complained of herein, individually and in their capacity as Police Officers of the Howard County Police Department, Defendants, 917 F.2d 1355

PHILLIPS, Circuit Judge: Howard County, Maryland, Police Officers William Pollack, Frank Salter, and Nancy Yeager appeal the district court’s interlocutory order denying them

summary judgment on qualified immunity grounds in Theresa Gooden’s claim against them under 42 U.S.C. § 1983. .Gooden brought this action against the officers, the county, and the county police chief after the officers seized her from her apartment and took her to a hospital for an emergency psychiatric evaluation.

Because the record discloses genuine issues of fact about the information the arresting officers reasonably had available, materially bearing on the ultimate legal question of whether they reasonably could have believed their actions lawful in light of clearly established law, we affirm the district court’s order. I The nature of our inquiry on this appeal necessitates a rather detailed

summary of the

summary judgment record. Denise Beck (now Denise Beck Stephens) has asserted by affidavit that in early 1987 she began hearing loud noises coming from the apartment above hers at the Chase Clary apartment complex in Columbia, Maryland. These noises, Beck stated in her affidavit, included loud screaming, yelling, and “general commotion.” J.A. at 47.

Uneasy about confronting the occupant of the apartment above her, J.A. at 47, Beck, a white woman, complained to the apartment manager, who in turn wrote a letter to Theresa Gooden, the black woman who occupied the apartment directly above Beck’s, asking that she keep the noise level to a minimum. J.A. at 130. Gooden, a 28-year old employee of the CIGNA Health Plan, had recently moved to Columbia from Michigan. At 8:30 a.m. on February 21, 1987, Beck called the police, asking them to respond to what Beck said she took to be a violent domestic dispute occurring in the overhead apartment.

She claims to have heard loud screaming and a female voice telling a male that her life had been ruined and that she would kill him. Howard County Police Officers Nancy Yeager and William Pollack, both white, responded to the call, first checking with Beck, then visiting Gooden's apartment overhead. Beck claims that the noises stopped once the officers made contact with Gooden. J.A. at 48. Upstairs, Officers Yeager and Pollack spoke briefly with Gooden. Gooden told them that she had been asleep and was awakened only by their loud knocking and that she neither caused nor even heard any disturbance.

J.A. at 30, 37, 51. Gooden claims that she consented to a search of her apartment, after which the officers, finding no one but her there, said that “obviously the screams were not coming from her apartment.” J.A. at 51. According to Gooden, Officer Pollack left, but Yeager stayed behind to question her, using an “accusatory and rude” tone. J.A. at 51. Yeager states that Gooden, though apparently cooperative, was “evasive and hesitant” in her answers. J.A. at 30.

Based on Beck’s certainty about having heard two voices, Yeager checked with the apartment manager and confirmed that, in fact, Gooden lived alone in the apartment. Gooden felt at the time that she was being targeted for racial harassment by someone in the apartment complex, and two days later reported the police’s visit to Officer David Steves of the Howard County Police. At about 10:30 p.m. on March 2, Beck again called the police complaining of noises from the apartment above. Officer Yeager, then on patrol with Officer Frank Salter, responded at 10:47 p.m. to the “woman screaming” call initiated by Beck.

Officers Yeager and Salter claim to have heard a loud “blood-chilling” scream upon entering the first level of the apartment building where Beck and Gooden lived, convincing them that someone was being harmed. J.A. at 30, 41. The officers went immediately to the third floor hallway and stood outside Gooden’s apartment. There, they claim to have heard another scream, this coming from within Gooden’s apartment. J.A. at 31, 42. Gooden answered the officers’ knock at her door. The police officers and Gooden give quite different accounts of the ensuing encounter.

According to Yeager, Goo-den, when first asked about the screaming, denied having made any noise, but then admitted that she had just burned herself ironing, and had screamed. J.A. at 31. Yeager states that she then asked to see the iron and ironing board, and discovered that there were no clothes on the ironing board and that the iron itself was cold to the touch. Yeager also states that she asked to see Gooden’s burn, and that Goo-den “just replied that it didn’t matter and finally totally refused to have me look at the burn.” J.A. at 31.

Yeager did not find the apartment disorderly, though she comments that it struck her as odd that Goo-den, who had described herself as a “loner” during the February 21 encounter, had “an inordinate number of cards and letters” displayed. J.A. at 31. Yeager stated in affidavit that she still believed that Gooden was not being candid and that in fact Goo-den was at risk of harm from herself or someone else. J.A. at 31-32. Gooden’s description of this encounter contrasts markedly with Yeager’s.

She explained that she had washed her laundry that evening until about 9:00 p.m. and was in her apartment for the next couple of hours, putting clothes away and ironing, most of the time talking on her cordless phone. While on the phone to a Marc Brogdon, some hot water from the iron splashed onto her arm, causing her to “yelp for a moment.” J.A. at 52. She then heard a loud knock on the door and, opening it, saw Yeager and Salter “crouching with billy clubs in hand.” She told Brogdon the officers were there and hung up.

According to Gooden, the officers accused her of screaming for the last two weeks, then unsuccessfully searched the apartment for another person. Upon questioning, Gooden explained that she had just yelped from an ironing spill, but that she did not think it loud enough to justify police intervention. In contrast to Yeager’s story, Gooden said that she showed the officers a blouse on the ironing board and a plugged-in iron, and moreover that she pointed out the wet spot on the blouse where water had spilled and the red mark on her arm, but that Yeager ignored them, demanding instead to see “a burn.” J.A. at 54.

Gooden states that as the officers were leaving, Salter said, “Next time we come, we’ll stay longer,” to which Gooden replied that they better have a warrant then. J.A. at 54. Yeager and Salter deny that Salter made any such comment. The officers went back downstairs to speak to Beck in her apartment. Soon thereafter, they heard and felt, it is claimed, the same noises and commotion from the apartment above that Beck had described: a male and female shouting at each other (but the two voices never shouting simultaneously), and “loud thuds” that caused even the chandelier in Beck’s apartment to shake. J.A. at 32.

Based on what she heard, Yeager thought that Gooden might have a “multiple personality,” talking back and forth in alternating male and female voices, and that she might be hurling herself against the walls. Gooden, however, claims that during the time just after the officers left she called her mother in Michigan and spoke for ten minutes. Her long-distance bill corroborates this. She then called Officer Denise Carter at the Howard County Police Department to inquire about registering a complaint concerning the officers’ visit. J.A. at 54.

Officer Carter stated in deposition testimony that she and Gooden had “a very calm conversation.” J.A. at 218. Assertedly because of what they had heard, Yeager and Salter returned to Goo-den’s apartment “after contacting all residents that were present in the building and failing to find any other source of the violence.” J.A. at 32.

According to Yeager, Gooden appeared to be crying when she answered the door and asked, “Why are you doing this to me?” Yeager pressed Gooden on her emotional state, but Gooden was “unresponsive,” offering no explanation for the screaming Yeager had heard and looking “nervous as well as uncomfortable” to Yeager. J.A. at 33. Sergeant Pollack and other backup officers had by then arrived on the scene and were in the hallway.

Yeager and Salter told Pollack that what they perceived as Gooden’s bizarre behavior — the possibility of a “split personality” with two voices talking to each other, the banging against the walls, and Gooden’s evasive failure to explain the noises — would justify petitioning for an emergency psychiatric evaluation. The officers filled out the petition, arrested and handcuffed Gooden, and transported her to a nearby hospital.

Gooden stated that when the officers handcuffed her behind her back, they refused to let her get a coat or purse and, despite her plea, would not make calls to verify her claim that she had not been screaming but instead had been on the phone with Marc Brogdon, her mother, and Officer Carter throughout the evening. Another resident of the apartment building, Patrick Cummings, offered affidavit testimony about what happened that evening. Cummings had never had any communication with Gooden, though when he had seen her, “she always appeared very professional and responsible.” J.A. at 71.

Cummings asserted that he saw police cars pulling into the building’s parking lot on March 2 and watched from his balcony. One officer asked him where the commotion was, and he pointed to the apartment directly below Beck’s, where a married white couple named Dowling lived. J.A. at 68. Cummings averred that his apartment shared parts of common walls with both Beck’s apartment and the Dowlings’ and that on that last night — and on many occasions before (and once after) — he had heard violent domestic disturbances from the Dowlings’ apartment.

Once he heard them screaming and saw shadows of what looked like a man and woman fighting. Another time on an early morning in late February, he heard a female voice shouting, “I’ve been married to you____ My life has been miserable. I don’t have any money. My life is ruined.” J.A. at 68. According to Cummings, Beck called for him and his wife to come tell the police what had been happening. As he went to Beck’s apartment, he saw Gooden being placed in the police car, and observed that she was speaking in a normal voice and, though upset, was “clearly not out of control.” J.A. at 69.

Cummings immediately told the officers at Beck’s apartment that they had the wrong person — that it was the Dowlings, not Gooden, who was making the noise. He stated that Beck, he, and his wife compared what they had heard and confirmed that it was in fact the Dowlings. Beck, he asserted, then exclaimed, “Oh my God, they took the wrong person.” J.A. at 70. (Beck, however, states in her affidavit that she believed then and continues to believe that the noise came from above her. J.A. at 48.) Cummings then led Officers Yeager and Pollack to the Dowlings’ apartment, directly below Beck’s.

As recounted in Yeager’s deposition testimony, Mr. Dowling had been drinking, and he and his wife had been fighting. J.A. at 149-50. Yeager told them to keep the noise down, filled out a report, and took no further action. J.A. at 150-51. Cummings concluded from all his discussions with and observation of the officers that they had a “preconceived notion” that Gooden had made the noise and “refused to believe anything that contradicted their belief.” J.A. at 70. None of the officers’ affidavits referred to the incident with Cummings and the Dowlings.

After waiting about two hours, Gooden was examined at Howard County General Hospital by Dr. Barton Hershfield. The doctor found no signs of mental illness. He noted further that Gooden did not appear disheveled and that she acted rationally and cooperatively during the examination. She was released after the examination, and declined a ride home offered by the police. Gooden brought an action against Howard County, the county police chief, and Officers Pollack, Salter, and Yeager.

She alleged that all of the defendants deprived her of her fourth and fourteenth amendment rights, and she sought damages under 42 U.S.C. § 1983. She claimed further that the police officers were liable under 42 U.S.C. § 1985(3) for engaging in a racially motivated conspiracy purposefully to deprive her of the equal protection of the laws. She also asserted pendent state law tort claims for assault, battery, and false arrest against the county and the officers. All defendants moved to dismiss the claims. The county argued that it was not liable on the

section 1983 claims because Gooden had failed to show that the officers’ conduct was attributable to a policy or custom of the county. The officers claimed qualified immunity. The district court treated the motions to dismiss as motions for

summary judgment and considered the affidavits and deposition testimony in the record. After hearing argument, the court held in an oral opinion that “viewing the facts and inferences in the light most favorable to the plaintiff, a jury could conclude that no reasonable officer could have believed in the lawfulness of subjecting Gooden to an involuntary psychiatric examination.” Tr. of Hearing on Motions to Dismiss at 65-66.

The court noted in particular several discrete factual issues that would bear directly on the objective legal reasonableness of the officers’ actions: (1) whether a reasonable officer would have concluded that Goo-den was a “multiple personality,” talking to herself in different voices and hurling herself against the wall, in light of evidence that she acted calmly and rationally, that neither she nor her apartment evidenced violent activity, and that a loud domestic disturbance was going on directly below Beck at the time; (2) whether a reasonable officer would have concluded that she was a danger to herself in light of evidence that she showed no signs of having been harmed in the intervals between the times the officers came to her apartment; and (3) whether a reasonable officer would have permitted Gooden’s continued detention after Patrick Cummings explained the incident to them.

Id. at 66-67. The court noted that if the jury believed all of Gooden’s evidence, the officers’ conduct would be “clearly unreasonable by any standard.” Id. at 67. After delivering his oral opinion, the district judge informally summarized his view of the case, based on the forecast of evidence in the record: “Let me say, and I expect my opinion pretty well spells it out ... if there was ever a case that cried for a trial, this is it____ On the face of everything I’ve read and everything I’ve heard, this is what juries are for.” Id. at 71.

The officers now appeal from an order denying a later motion to amend or alter judgment. II The officers contend that the district court erred in denying them

summary judgment based on qualified immunity. Specifically, they contend that the law governing the seizure of a person for an emergency psychiatric evaluation was not so clearly established that a reasonable officer could have known what conduct the Constitution proscribed. Alternatively, they contend that if we find that the law was “clearly established” in this area, we should hold as a matter of law that a reasonable officer could have believed this conduct lawful. We briefly review the principles that guide our consideration of the qualified immunity defense when asserted in a

summary judgment motion, then address these alternative contentions. A The defense of qualified immunity generally protects “government officials performing discretionary functions ... from liability for civil damages insofar as their conduct does not violate clearly established statutory or constitutional rights of which a reasonable person would have known.” Harlow v. Fitzgerald, 457 U.S. 800, 818, 102 S.Ct. 2727, 2738, 73 L.Ed.2d 396 (1982). Qualified immunity thus affords a defendant government official broader protection than does the merits defense that no constitutional violation occurred.

Regardless of whether the constitutional violation occurred, the defendant should prevail if the right asserted by the plaintiff was not “clearly established,” in the “particularized” sense that “[t]he contours of the right [were] sufficiently clear that a reasonable official would understand that what he is doing violates that right.” Anderson v. Creighton, 483 U.S. 635, 640, 107 S.Ct. 3034, 3039, 97 L.Ed.2d 523 (1987).

Even where the rights allegedly violated may be clear at some level of abstraction, the defendant should prevail if a reasonable officer could have believed his particular conduct lawful, a standard requiring a court to undertake an “objective (albeit fact-specific)” inquiry into the legal reasonableness of the conduct. Id. at 641, 107 S.Ct. at 3040.

The qualified immunity test thus necessitates three discrete determinations: the identification of the specific right allegedly violated, the determination of whether that right was so “clearly established” as to alert a reasonable officer to its constitutional parameters, and the ultimate determination of whether a reasonable officer could have believed lawful the particular conduct at issue. Collinson v. Gott, 895 F.2d 994, 998 (4th Cir.1990) (Phillips, J., concurring). The first two determinations present pure questions of law.

The third, though ultimately a legal question, may require subsidiary factual determinations. If a reasonable officer could have believed his conduct legal under one version of what occurred, but could not have so believed under a conflicting version of the conduct, then further factual development will be necessary. Id. Often trial can yet be avoided if carefully limited discovery reveals that there are no genuine issues of fact concerning the conduct at issue, permitting the court then to rule as a matter of law on the third and ultimate question.

See Anderson, 483 U.S. at 646 n. 6, 107 S.Ct. at 3042 n. 6 (1987). In some instances, however, material subsidiary questions of fact regarding an official’s conduct, or the information he reasonably possessed at the time he acted, will still be genuinely in dispute after full discovery, and

summary judgment must be denied. In reviewing an immediately appealable interlocutory order denying

summary judgment, we review both the pure legal issues respecting the existence of clearly settled constitutional law in relation to the defendant’s conduct, and also whether there are genuine issues of material fact respecting the official’s conduct which require resolution before its objective reasonableness can be assessed. Turner v. Dammon, 848 F.2d 440, 445-47 (4th Cir.1988).

B The officers first contend that they should prevail on qualified immunity because the paucity of cases discussing constitutional standards for a seizure preliminary to an emergency psychiatric evaluation suggests that there was no clearly established law guiding their conduct. This lack of case law guidance, they suggest, created a “legitimate question,” see Tarantino v. Baker, 825 F.2d 772, 775 (4th Cir.1987), whether a fourth amendment standard lower than probable cause to arrest might apply to a situation where the police act on a perceived psychiatric emergency.

At the outset, we note that the parties agree that the source of Gooden’s constitutional right against what occurred here was the fourth amendment. Although confinement by state action of the mentally ill is generally analyzed under the due process clause of the fourteenth amendment, see O’Connor v.

Donaldson, 422 U.S. 563, 573-76, 95 S.Ct. 2486, 2492-94, 45 L.Ed.2d 396 (1975) (state cannot constitutionally confine a nondangerous mentally ill person capable of living safely in freedom), we address here the analytically distinct right to be free from an unreasonable governmental seizure of the person for whatever purpose. A citizen enjoys that right regardless of the purpose for which the state acts, see In re Barnard, 455 F.2d 1370, 1373 (D.C.Cir.1971) (“[T]he Fourth Amendment’s prohibition is not limited to cases involving arrests.”); Brown v.

Fauntleroy, 442 F.2d 838, 842 (D.C.Cir.1971) (in juvenile case where defendant in custody of mother, court found “the right to be free of a seizure made without probable cause does not depend upon the character of the subsequent custody”), and although the right may overlap somewhat with the right to due process, governmental conduct amounting to seizure of the person must be scrutinized under the more specific rules deriving from the fourth amendment. See Fisher v. Washington Metro Area Transit Auth., 690 F.2d 1133, 1138 & n. 5 (4th Cir.1982); McKinney v. George, 726 F.2d 1183, 1187 (7th Cir.1984).

As indicated, the officers do not contest the general applicability of the fourth amendment, but argue that the lack of case law applying fourth amendment standards in the context of seizure of the mentally ill gave rise to a “legitimate question” about whether some standard lower than probable cause might justify such a seizure as reasonable. Without suggesting that

summary judgment would be warranted if a lower standard did apply, we simply do not think there was a legitimate question on this point. We have found few cases that discuss the fourth amendment standard in the context of seizure of the mentally ill, but all have recognized the otherwise plainly evident proposition that such a seizure is directly analogous to a criminal arrest and must therefore be supported by probable cause. See, e.g., In re Barnard, 455 F.2d at 1373; McKinney, 726 F.2d at 1187; Harris v. Pirch, 677 F.2d 681, 686 (8th Cir.1982).

Indeed, a federal court in these officers’ own district had earlier noted, as though it were self-evident, the applicability of the federal constitutional probable cause standard in the mental health seizure context. In Gross v. Pomerleau, 465 F.Supp. 1167 (D.Md.1979), a plaintiff sued a police officer who arrested her and committed her briefly to a psychiatric unit after she, according to the officer’s account, became hysterical during a routine traffic stop.

The district court observed that the question of an underlying constitutional violation would turn on whether the officer had probable cause to believe in the woman’s need for emergency psychiatric evaluation. Gross, 465 F.Supp. at 1171 (“At issue, then, is whether plaintiff’s behavior at the time of the arrest was sufficient to justify a finding of probable cause for her eventual commitment to the Unit.”).

In its analysis of police department procedures for making such a seizure, the court noted the lack of any meaningful distinction between the procedures that govern seizure preceding civil commitment and those governing criminal arrest of a mentally ill person. Id. at 1172 (“common sense suggests that both procedures were intended to deal with the same type of individual, i.e., the mentally disturbed person, although in different contexts”).

The gravity of the constitutional harm to a person wrongly seized for mental illness lay behind the court’s concern for requiring proper procedural and substantive standards before such a seizure. Id. at 1173 (“Commitment to an Evaluation Unit, even for a day, involves a loss of liberty, privacy, free association and could well have the effect of creating a stigma against the person confined.”); id. (such a deprivation can create “a stigma of mental illness which can be as debilitating as that of criminal conviction”) (quoting Stamus v. Leonhardt, 414 F.Supp. 439, 444 (S.D.Iowa 1976)).

In sum, we think the fourth amendment’s applicability in this situation was sufficiently “clearly established” that no reasonable officer could have believed it lawful to seize Gooden unless he had probable cause to believe that she was both mentally ill and that her mental illness made her a danger to herself or others. See O’Connor, 422 U.S. at 575-76, 95 S.Ct. at 2493-94. As noted, however, the existence of this “clearly established” law does not end our inquiry on

summary judgment; the question remains whether there exist on the record as a whole genuine issues of material fact bearing on the objective legal reasonableness of the officers’ actions in light of the law. Turner, 848 F.2d at 444. The availability of qualified immunity turns not on whether the officers actually had probable cause but whether the circumstances made it reasonable for them to think they did.

Their immunity defense therefore depends critically and inescapably on resolution of factual questions about what circumstances reasonably appeared to the officers, what information they reasonably could be expected to have had and gathered, and what conclusions they reasonably could have reached and acted on in those circumstances and with that information. See Sevigny v. Dicksey, 846 F.2d 953, 957 (4th Cir.1988) (qualified immunity defense may turn on factual determinations about how a reasonably informed officer, acting reasonably under the circumstances, would have perceived the unfolding events).

As we think our detailed account of the facts of record shows, and as the district court cogently pointed out in denying

summary judgment, a number of critical facts remain hotly disputed at this stage. Without recapitulating the welter of conflicting versions of the critical events leading to Gooden’s being taken into custody, it suffices to point out that if the reality of what was taking place at the times in issue was as Gooden’s evidence tends to show, it is fairly disputable whether these officers reasonably could have perceived things to be as they testified they were.

More specifically, if Cummings’ version of events were accepted — that the probable source of the noises of altercation upon which the officers acted was the Dowlings’ quarters rather than Gooden’s and that Cummings so advised the officers who then failed to verify this possibility — it is fairly disputable whether they reasonably could have believed their conduct to be justified.

See Sevigny, 846 F.2d at 957 & n. 5 (in assessing reasonableness of officer’s perception of probable cause to arrest, officer must be charged with knowledge of relevant facts readily available to officer acting reasonably under circumstances). Resolution of these and related factual issues can only be made on the basis of credibility determinations respecting flatly conflicting versions of critical historical facts. As the district court aptly put it, “this is what juries are for.” Despite the desirability of resolving qualified immunity claims without trial, that sometimes is not possible.

In such cases, this extraordinary defense, still more favorable than a defense on the merits, see Sevigny, 846 F.2d at 956 & n. 3, must be submitted to a trier of fact. In so holding here, we of course express no opinion as to how it should there be resolved. AFFIRMED . The officers technically appeal from a later order denying a motion to alter or amend judgment. The district court had treated the officers’ motion to dismiss as a motion for

summary judgment, and we have jurisdiction to review an order denying

summary judgment on qualified immunity grounds under 28 U.S.C. § 1291. Mitchell v. Forsyth, 472 U.S. 511, 105 S.Ct. 2806, 86 L.Ed.2d 411 (1985). To the extent the officers may seek to challenge other aspects of the order going to the merits of other claims, we lack jurisdiction to address any such challenge. . A U.S. Sprint long-distance bill shows a call from Gooden's number to Brogdon's in Michigan between exactly 10:00 to 10:55 on that evening. In affidavit testimony, Brogdon stated that Gooden at one point said "ow" into the phone, then explained that she had just burned herself with an iron.

Brogdon also stated that he had heard the knock on the door and the police identifying themselves and saying they were responding to a noise complaint. J.A. at 64. . Such a “seizure," including that which indisputably occurred here, obviously has the same degree of intrusiveness on one’s freedom of movement as an "arrest,” and in this critical respect is distinguished from the less intrusive "investigative stop” that may be justified by a mere "articulable suspicion.” See Terry v. Ohio, 392 U.S. 1, 15-16, 88 S.Ct. 1868, 1876-77, 20 L.Ed.2d 889 (1968).

The critical distinction between the degrees of suspicion or belief required to justify the one type of seizure as against the other, and the fact that "probable cause” is the unquestioned standard for the more intrusive, see, e.g., Gerstein v. Pugh, 420 U.S. 103, 111, 95 S.Ct. 854, 861, 43 L.Ed.2d 54 (1974), were obviously well-settled constitutional principles of which reasonable police officers would have known at the times here in issue.

Put another way, no reasonable police officer could have thought that taking Gooden against her will for a psychiatric evaluation was more akin to a mere investigative Terry stop than to a complete seizure by "arrest” for a state's custodial purposes. . In its ultimate ruling on the officer’s and city’s

summary judgment motion based on qualified immunity, the Gross court stated that the seizure was unconstitutional because a police commissioner memorandum on emergency psychiatric admissions set forth an impermissibly vague definition of mental illness. The court denied the officer qualified immunity under the now-abandoned, pre-Harlow, subjective good faith standard because it found genuine issues of material fact as to whether, under the circumstances of the arrest, the officer had relied in good faith on the unconstitutional procedures. The court did, however, grant

summary judgment to the city, finding that the record entitled them to good faith immunity. Id. at 1175. This grant of qualified immunity to the city of course preceded the Supreme Court's decision in Owen v. City of Independence, 445 U.S. 622, 100 S.Ct. 1398, 63 L.Ed.2d 673 (1980) (municipalities do not enjoy qualified immunity from § 1983 liability). .

Of added significance to the state-of-the-law inquiry is the fact that Maryland statutory law, of whose constraints a reasonable police officer in the state surely must be charged with knowledge, contemplates a "probable cause" standard for commitment for emergency psychiatric evaluation. See Md. Health-Gen.

Code Ann. §§ 10-623 (probable cause determination by court required for commitment on petition of lay person); 10-622(a), (b)(2) (peace officer "who personally has observed" the subject and has “reason to believe” in grounds for commitment, may petition therefor); 10-624(a) (duty of peace officer to "take” subject for evaluation when armed with "reasonable cause" petition).

While state law does not define federal fourth amendment standards for seizures of the person by state actors, see Fisher, 690 F.2d at 1138 & n. 5 (arrest), where, as here, the two are the same, a reasonable police officer’s necessary awareness of the contours of the state standards perforce embraces awareness of the federal standard. In this sense, the contours of the federal probable cause standard for this type of seizure must be considered well-settled so far as a reasonable officer in Maryland is concerned. .

The dissent opines, at 1367, that "[t]he majority’s view of qualified immunity will produce a triable issue, under

section 1983 whenever the police commit an error.” We of course adopt no such view. Our holding — as any fair reading would demonstrate — is only that where the reasonableness of police error is in genuine issue,

summary judgment is inappropriate. In contrast, the dissent apparently would always accept police officers’ versions of what they perceived that caused them to err, even where, as here, their version has been put in genuine factual issue. This is reflected most dramatically in the dissent’s statement, at 1366, that "these officers indisputably perceived ... that harrowing screams were coming from Goo-den’s apartment.” The only thing undisputed on the

summary judgment record about the source of any "harrowing screams” on which these officers acted is that one person had told the officers that they came from Gooden’s apartment and that from that point on the officers accepted that account and acted on it. The accuracy of that perception and the reasonableness of the officers' continued acceptance of it (the dispositive issue here) is precisely what is put in genuine factual issue by the opposing accounts later given the officers by Gooden herself, and by Cummings.

What may start out as a reasonable mistake in perception may become unreasonable as events of this kind unfold. And it is reasonableness in the end that counts. In this connection, it is critical to keep in mind that the drastic mistake concededly made here was not one made in a rush of life-threatening events, see Sevigny, 846 F.2d at 957 & n. 6 (exigency may, but did not in instant case, excuse mistake in perceiving probable cause), but was one formed over an extended period of time and under no pressure to act quickly in order to protect either the officers or others from physical harm or to prevent escape.

Id. The only threats to anyone according to the officers’ own version were (1) to Ms. Beck’s peace of mind, and (2) to Gooden herself — a threat that turned out to exist only in the police officers’ bizarre medical theory of a split personality disorder to explain the otherwise inexplicable presence of a single, apparently unruffled female at the presumed source of the "harrowing screams.” Surely the watchword of reasonableness in this situation was extreme caution and care for citizens’ rights rather than precipitate action in discharge of dangerous duty.

Whether sufficient care and caution was exercised in getting the critical facts is precisely the genuine issue of material fact that stubbornly remains.