This case represents a further development in the burgeoning field of civil rights actions brought under 42 U.S.C.A. § 1983 by state prisoners who have not exhausted their state remedies by first attacking their conviction and confinement in state courts. We hold that a § 1983 action for damages based on the withholding at trial of possible exculpatory evidence by state officials in violation of Brady v. Maryland, 373 U.S. 83, 83 S.Ct. 1194, 10 L.Ed.2d 215 (1963), cannot be prosecuted while the state case is on appeal and before all state remedies have been exhausted in seeking relief from the conviction allegedly obtained in violation of the federal Constitution and law. Concerned about the possible statute of limitations bar to a suit not commenced until after such exhaustion, however, we vacate the district court’s order of dismissal and remand for consideration of whether the suit should be held in abeyance, rather than dismissed.
In 1974 plaintiff was convicted of murder and sentenced to life imprisonment. His appeal from this conviction was pending before the Louisiana Supreme Court when this case was heard. Twice during the course of his trial petitioner moved that the court require the prosecution to furnish exculpatory evidence, and both times the prosecution responded that they had none. Seeking money damages from two assistant district attorneys and the superintendent of police for violation of his constitutional rights in allegedly refusing to divulge *379exculpatory evidence which plaintiff asserts was in their possession, Fulford filed this § 1983 suit. Before any response from defendants, the court dismissed the complaint without prejudice, ruling that “since the petitioner challenged the legality of his imprisonment, we should treat this as a habeas corpus petition and require that Fulford exhaust his state remedies.”
Asserting that he is not attacking the validity of his conviction in this suit, nor seeking release from state confinement, plaintiff claims that he is entitled to bring a § 1983 civil suit for damages without first being forced to seek habeas corpus relief with its concomitant requirement of exhaustion of state remedies under 28 U.S.C.A. § 2254.
The district court properly relied on our decision in Alexander v. Emerson, 489 F.2d 285 (5th Cir. 1973). Plaintiff asserts that Alexander is wrong and should be reversed. One panel of this Court cannot overrule a decision of a previous panel, absent controlling Supreme Court authority. Only the Court en banc may do that. See F.R.A.P. Rule 35; United States v. Lewis, 475 F.2d 571, 574 (5th Cir. 1972). A reexamination of Alexander, however, in the light of two recent Supreme Court cases, Wolff v. McDonnell, 418 U.S. 539, 94 S.Ct. 2963, 41 L.Ed.2d 935 (1974) and Preiser v. Rodriguez, 411 U.S. 475, 93 S.Ct. 1827, 36 L.Ed.2d 439 (1973), convinces us that the principle there announced remains sound, at least as applied to the facts of this case. Any further reevaluation of Alexander is unnecessary.
The Alexander Court gave full imprimatur to Smith v. Logan, 311 F.Supp. 898 (W.D.Va.1970). There the plaintiff, a prisoner, brought a § 1983 civil rights suit for damages caused by the use of perjured testimony to convict him in a prior criminal trial. The district judge stated that “it would be improvident for a federal court to entertain a suit for damages inquiring into possible constitutional violations committed during the trial, while petitioner is imprisoned on that conviction.” 311 F.Supp. at 899. Quoting the opinion at length, Alexander applied this concept in dismissing a damage suit, brought before exhaustion, in connection with alleged constitutional infirmities in an arrest, search and seizure leading to the introduction at plaintiff’s criminal trial of the property seized.
This case is controlled a fortiori by the decision in Alexander. Like Smith v. Logan, the sole complaint here concerns a constitutional right which accrues only during a criminal prosecution, i. e., the due process right to examine for trial purposes exculpatory evidence in possession of the prosecutor. An illegal arrest or search and seizure, the source of the Alexander litigation, may support a cause of action for damages independent of any criminal charge or trial. The rights asserted here to a fair trial and to due process of law are, on the other hand, by their nature cognizable only in the context of the validity of the criminal proceeding. By requiring that exhaustion of state remedies precede a civil rights action in a case where the damage may be both related and unrelated to the underlying criminal conviction, the rule clearly applies to the alleged abuse of rights involving only the trial and the criminal conviction itself. The Supreme Court decisions of Preiser and Wolff sharpen our focus on this issue, but do not preclude the application of Alexander to cases such as the one before us today, where the gravamen of the plaintiff’s argument is that his underlying criminal conviction was unconstitutionally obtained.
An examination into the relationship between civil rights and habeas corpus actions must be made with an understanding of the requirement of exhaustion of state remedies pertaining to the habeas corpus relief, and the underlying doctrine of comity between state and federal judicial systems. Compelled by the “exigencies of federalism,” the doctrine of comity dictates that a federal court “defer action on cases properly within its jurisdiction until the courts of another sovereignty with concurrent powers, and already cognizant of the litigation, have had an opportunity to pass upon the matter.” Fay v. Noia, 372 U.S. 391, 415, 420, 83 S.Ct. 822, 839, 9 L.Ed.2d 837, 857 (1963), citing Darr v. Burford, *380389 U.S. 200, 204, 70 S.Ct. 587, 590, 94 L.Ed. 761, 767 (1950).
There is little question that civil remedies based on the violation of federal rights may be sought in federal court without exhaustion of state court remedies where the federal remedy is independent of any kind of habeas corpus relief or is merely supplementary to possible state action. In Monroe v. Pape, 365 U.S. 167, 183, 81 S.Ct. 473, 481, 5 L.Ed.2d 492, 502 (1961), the Supreme Court held that plaintiffs had properly stated a cause of action under 42 U.S. C.A. § 1983 against 13 policemen for damages resulting from an unconstitutional search which did not lead to criminal action. Exhaustion of state remedies was not necessary: “it is no answer that the State has a law which if enforced would give relief. The federal remedy is supplementary to the state remedy, and the latter need not be first sought and refused before the federal one is invoked.” Id. at 183, 81 S.Ct. at 482, 5 L.Ed.2d at 503. In Wilwording v. Swenson, 404 U.S. 249, 92 S.Ct. 407, 30 L.Ed.2d 418 (1971), the Court held that a prisoner’s suit charging that prison conditions worked a deprivation of constitutional rights properly pleaded a cause of action under 42 U.S.C.A. § 1983 and that exhaustion was not required. See also Houghton v. Shafer, 392 U.S. 639, 88 S.Ct. 2119, 20 L.Ed.2d 1319 (1968); King v. Smith, 392 U.S. 309, 88 S.Ct. 2128, 20 L.Ed.2d 1118 (1968); Damico v. California, 389 U.S. 416, 88 S.Ct. 526, 19 L.Ed.2d 647 (1967); McNeese v. Board of Education, 373 U.S. 668, 83 S.Ct. 1433, 10 L.Ed.2d 622 (1963).
In Preiser v. Rodriguez, supra, the Supreme Court directly confronted the conflict between habeas corpus and civil rights actions. That case involved three § 1983 actions brought by New York state prisoners who alleged unconstitutional deprivation of good time credits because of unconstitutional state administrative action and sought injunctive relief to compel restoration of the credits. The plaintiffs filed their § 1983 complaints in combination with petitions for writ of habeas corpus. Referring to the “strong policy” of supporting federal-state comity by requiring exhaustion, the Court ruled that when cases fall squarely within the traditional bounds of habe-as corpus, a § 1983 action is not a permissible alternative. To quote at length from that opinion:
The respondent’s counsel acknowledged at oral argument that a state prisoner challenging his underlying conviction and sentence on federal constitutional grounds in a federal court is limited to habeas corpus. It is clear to us that the result must be the same in the case of a state prisoner’s challenge to the fact or duration of his confinement, based, as here, upon the alleged unconstitutionality of state administrative action. Such a challenge is just as close to the core of habeas corpus as an attack on the prisoner’s conviction, for it goes directly to the constitutionality of his physical confinement itself and seeks either immediate release from that confinement or the shortening of its duration. ... It would wholly frustrate explicit congressional intent to hold that the respondents in the present case could evade [exhaustion of state remedies] by the simple expedient of putting a different label on their pleadings.
411 U.S. at 489-490, 93 S.Ct. at 1836, 36 L.Ed.2d at 450.
The Court then went on, however, to hold that a damage claim which does not both attack the confinement and seek release may proceed without prior exhaustion of state remedies.
If a state prisoner is seeking damages, he is attacking something other than the fact or length of his confinement, and he is seeking something other than immediate or more speedy release — the traditional purpose of habe-as corpus. In the case of a damages claim, habeas corpus is not an appropriate or available federal remedy. Accordingly, petitioners themselves concede, a damages action by a state prisoner could be brought under the Civil Rights Act in federal court without any requirement of prior exhaustion of state remedies. Cf. Ray v. Fritz, 468 F.2d 586 (CA2 1972).
*381Id. 411 U.S. at 494, 93 S.Ct. at 1838, 36 L.Ed.2d at 453. It is not clear from this decision whether an attack on the confinement where release is not sought but damages are requires exhaustion.
In Wolff v. McDonnell, supra, the Supreme Court later held that prisoners who challenged prison disciplinary procedures and requested money damages, in-junctive restoration of good time credits and submission of a plan for a prison hearing procedure in a class action had only a limited § 1983 cause of action. The Court found that restoration of good time credits was foreclosed under the authority of Preiser. Nevertheless, the claim for damages arising from allegedly invalid disciplinary procedures could go forward while actual restoration of good time credits was concurrently sought in state proceedings. Although the opinion is unclear as to whether the loss of good time credits could be claimed as an element of damages, we do not believe the Court so intended. The Supreme Court ruled that on remand the district court was foreclosed from issuing an injunc-tive restoration of good time credits, but could assist a plaintiff in obtaining “ancillary relief” by enjoining the prospective enforcement of invalid prison regulations. 418 U.S. at 554-555, 94 S.Ct. at 2973, 41 L.Ed.2d at 949.
From the Court’s delineation of permissible and impermissible uses of the district court’s injunctive and declaratory powers on remand of the Wolff case, we conclude that the Court authorized the district court to examine the constitutionality of the state prison procedure, and to award damages which were incidental to an invalid proceeding. Since the district court was expressly forbidden to enter an injunction concerning the merits of the issue before the state administrative body (i. e., the proper length of confinement), however, it follows as a matter of logic that the district court was similarly prohibited from awarding damages for excessive confinement.
On our reading of Wolff and Preiser we reject Fulford’s argument that the propriety of § 1983 actions may be determined solely on the basis of the relief sought, i. e., actions for money damages may go forward while actions for injunctive relief from incarceration may not. We conclude from the Supreme Court cases that habeas corpus is the exclusive initial cause of action where the basis of the claim goes to the constitutionality of the state court conviction.
The strong policy of comity between state and federal judicial systems buttresses the decision we reach in the instant case. See also Guerro v. Mulhearn, 498 F.2d 1249 (1st Cir. 1974). Comity was succinctly defined in Younger v. Harris, 401 U.S. 37, 44, 91 S.Ct. 746, 750, 27 L.Ed.2d 669, 675 (1971), as “a proper respect for state functions.” It would be the height of disrespect for the integrity of the administration of justice in Louisiana if we were to attempt to decide, during the pendency of an appeal from a criminal conviction and prior to the pursuit of state habeas corpus remedies, whether a prisoner should be given damages because of a denial of the constitutional right to due process during his criminal trial. Indeed if we were to believe that on remand from the Wolff v. McDonnell opinion the district court could determine that a prisoner was entitled to the good time credits that the disciplinary body had cancelled, and could award money damages therefor, any concurrent state action would be an exercise in futility. Clearly plaintiff’s assertion that his Brady rights were violated, although asking money damages, is a thinly disguised circumvention of state remedies. We note that the result of the Brady holding was reversal of plaintiff’s criminal conviction and not the award of money damages at civil law. Brady did not create any cause of action independent of the validity of the conviction.
The district court in Smith v. Logan, supra, intimated that a § 1983 action was entirely improper, not just untimely. We pretermit a decision on whether this aspect of the Smith v. Logan holding has been adopted by this Circuit. For reasons akin to comity, and based on the requirements for a case and controversy, and for judicial economy, the question is *382not ripe at this stage in the litigation of Fulford’s claim. Any consideration of whether Fulford could have a cause of action for damages, even after exhaustion, must await final determination of the validity of the conviction in state court.
On this appeal Fulford argues that by requiring him to pursue habeas corpus relief and to exhaust state remedies, his right to seek § 1983 relief may be prejudiced by the running of the relevant Louisiana liberative prescription (statute of limitations). See Shank v. Spruill, 406 F.2d 756 (5th Cir. 1969); Still v. Nichols, 412 F.2d 778 (1st Cir. 1969). Since we do not hold that a § 1983 action is necessarily impermissible, we share petitioner’s concern that the trial court’s disposition—dismissal without prejudice—might as a practical matter preclude a future civil rights action on this cause. Possibly the mere fact that Fulford brought this apparently timely civil rights action, regardless of its present disposition, tolls the limitation period. Alternatively, Fulford’s status as a prisoner may toll the running of the limitation period under a disability provision in the relevant prescriptive statute. Or possibly the only means for the district court to protect petitioner’s right is to stay the § 1983 action pending the outcome of the state court appeal, and a possible habeas corpus appeal before the federal courts. See Mastracchio v. Ricci, 498 F.2d 1257 (1st Cir. 1974), cert. denied, 420 U.S. 909, 95 S.Ct. 828, 42 L.Ed.2d 838 (1975). This matter, which involves application of the state’s statute of limitations, see, e. g., O’Sullivan v. Felix, 233 U.S. 318, 34 S.Ct. 596, 58 L.Ed. 980 (1914); Shank v. Spruill, supra; Mulligan v. Schlachter, 389 F.2d 231 (6th Cir. 1968), is best left to the district court for its initial consideration and decision.
We therefore affirm the district court’s holding that a civil rights action under 42 U.S.C.A. § 1983, if any, is not properly before the Court at this time because it involves an issue which goes to the constitutionality of petitioner’s presently valid conviction, but we vacate the order that the case be dismissed, and we remand for reconsideration in light of the statute of limitations problem. Vacated and remanded.