Is it constitutional for a court to enforce a subpoena of ministers' sermons?

The Houston Chronicle reports (see also Prof. Josh Blackman's post):

Houston's embattled equal rights ordinance took another legal turn this week when it surfaced that city attorneys, in an unusual step, subpoenaed sermons given by local pastors who oppose the law and are tied to the conservative Christian activists that have sued the city.

Opponents of the equal rights ordinance are hoping to force a repeal referendum when they get their day in court in January, claiming City Attorney David Feldman wrongly determined they had not gathered enough valid signatures to qualify for the ballot. City attorneys issued subpoenas last month during the case's discovery phase, seeking, among other communications, "all speeches, presentations, or sermons related to HERO, the Petition, Mayor Annise Parker, homosexuality, or gender identity prepared by, delivered by, revised by, or approved by you or in your possession."

1. In principle, I don't think there's a First Amendment bar to subpoenaing the text (or video or audio recordings) of sermons, if they are sufficiently relevant to a case or an investigation.

Say, for instance, that someone sues, claiming that a minister slandered him in a sermon, for instance urging people not to patronize his business because he was supposedly guilty of a crime (a falsehood, it turns out). If the allegations were factual claims, not theological judgments, and especially if the plaintiff wasn't a member of the congregation, that may well be slander. (It might be slander even if the target is a member of the congregation, but there's some lower court disagreement on that.) It seems to me that the plaintiff may subpoena the text of the sermon, or, better yet, a recording that the minister made of the sermon, as evidence of what the minister said, or of what he knew at the time he said it.

True, the sermon is protected by the First Amendment; but so are conversations in a newspaper editorial meeting, and Herbert v. Lando (1979) holds that such conversations can be subpoenaed. There's no reason why the Free Exercise Clause would provide a greater protection against subpoenas of the sermon than the Free Speech/Press Clause provides against subpoenas of participants in the newspaper editorial meeting. Indeed, the case for barring subpoenas of the sermon is, if anything, weaker than the case for barring subpoenas of the editorial conversations, since sermons are generally not intended to be confidential; but in any case, neither is protected against subpoena, I think.

Likewise, say that a fired employee of a church, who had no religious duties, sues for sex discrimination. (Because the employee had no religious duties, there's no constitutional barrier to the lawsuit itself.) And say that she has heard that the minister said in a sermon that he fired her because (for instance) she was about to have a child, and he thinks that women with children should stay home. There too the plaintiff may subpoena the text or recording of the sermon, to use as evidence in the trial. University of Pennsylvania v. EEOC (1990) held that discrimination plaintiffs may subpoena records of tenure peer review materials, notwithstanding the possibility that such disclosure would interfere with the university's First Amendment rights. The materials are themselves constitutionally protected speech, and they influence retention and promotion decisions that in turn affect the university's speech; but the Court held that there is no First Amendment barrier to such subpoenas. I would think that the same logic would apply to churches.

To be sure, associations generally can't be required to turn over their membership lists (NAACP v. Alabama (1958)). And DeGregory v. New Hampshire (1966) held that the First Amendment could bar ordering a person to report on "the views expressed and ideas advocated" at political gatherings (there, Communist gatherings). But since then, the Court has generally not extended NAACP v. Alabama beyond membership lists, or situations where the information was at most marginally relevant to an investigation or a case—situations in which the government was "prob[ing] at will and without relation to existing need" (to quote the way Branzburg v. Hayes (1972) characterized DeGregory).

2. But all this presupposes that the information in the subpoenaed sermons really is substantially relevant to a case or an investigation. I don't quite see how "all speeches, presentations, or sermons related to HERO, the Petition, Mayor Annise Parker, homosexuality, or gender identity prepared by, delivered by, revised by, or approved by you or in your possession" would be relevant to the litigation about the validity of the referendum petitions.

At the very least, the subpoena seems vastly overbroad. And the fact that it seeks the contents of religious speeches does counsel in favor of making the subpoena as narrow as possible (which would likewise be the case if it sought the contents of political speeches). I'm not sure what sort of legally relevant information might be contained in the subpoenaed sermons. But the subpoena ought to be narrowed to that legally relevant information, not to all things about homosexuality, gender identity, the mayor, or even the petition or the ordinance.

Justice Powell's concurring opinion in Branzburg v. Hayes (1972) is helpful here. Justice Powell joined the majority in that case, concluding that there was no broad First Amendment journalist's privilege to conceal the names of confidential sources; but he concurred to point out that some subpoenas for such names should be suppressed (paragraph break and emphasis added):

As indicated in the concluding portion of the opinion, the Court states that no harassment of newsmen will be tolerated. If a newsman believes that the grand jury investigation is not being conducted in good faith he is not without remedy.

Indeed, if the newsman is called upon to give information bearing only a remote and tenuous relationship to the subject of the investigation, or if he has some other reason to believe that his testimony implicates confidential source relationships without a legitimate need of law enforcement, he will have access to the court on a motion to quash and an appropriate protective order may be entered. The asserted claim to privilege should be judged on its facts by the striking of a proper balance between freedom of the press and the obligation of all citizens to give relevant testimony with respect to criminal conduct. The balance of these vital constitutional and societal interests on a case-by-case basis accords with the tried and traditional way of adjudicating such questions.

Replacing "newsman" with "minister" (and making related changes) should provide a helpful guide to this case. And while sermons are generally not intended to be as confidential as the names of journalists' sources, there is still good reason to limit demands for the text of sermons when the text is irrelevant and therefore unnecessary to any legal decisionmaking. Such demands create a feeling of surveillance that may indeed deter or dampen some kinds of religious speech. And while such deterrence or dampening is constitutional when relevant information is subpoenaed (just as it's constitutional as to subpoenas related to editorial meetings and tenure reviews), it should be avoided and minimized in cases where the subpoenaed information is entirely or largely legally irrelevant.

3. One more twist: Texas has a Religious Freedom Restoration Act, under which "a government agency may not substantially burden a person's free exercise of religion" unless "the application of the burden to the person … is the least restrictive means of furthering [a compelling governmental interest]." So if a minister does feel a religious compulsion or even a religious motivation not to reveal the text of sermons, then he could only be required to turn over the sermons if the government passes the "least restrictive means" test. (How that test would play out is hard to tell, though again much depends on how relevant the information is likely to be, and also on whether there are other effective ways of getting it.)

But if a minister—even if he thinks the demand for the sermons is outrageous, intrusive, and unconstitutional—doesn't actually think that turning over the sermons would be religiously wrong, then he wouldn't have a Texas RFRA defense.

UPDATE: Here are the subpoena request and the memorandum in support of the motion to quash the subpoenas.