Defendant-appellant Daniel Baker appeals from an interlocutory order of the district court denying his motion to dismiss and motion for partial summary judgment. On appeal, Baker contends (1) that the district court incorrectly applied the “law of the case” doctrine and (2) that he is entitled to absolute immunity from civil liability for testimony he provided to the grand jury of El Paso County, Colorado and to the state trial judge in a preliminary hearing.
We have jurisdiction over an interlocutory decision denying absolute immunity under the “collateral order” doctrine. See Nixon v. Fitzgerald, 457 U.S. 731, 102 S.Ct. 2690, 73 L.Ed.2d 349 (1982); Helstoski v. Meanor, 442 U.S. 500, 506-08, 99 S.Ct. 2445, 2448-49, 61 L.Ed.2d 30 (1979); Abney v. United States, 431 U.S. 651, 657-63, 97 S.Ct. 2034, 2038-43, 52 L.Ed.2d 651 (1977); Cohen v. Beneficial Indus. Loan Corp., 337 U.S. 541, 546-47, 69 S.Ct. 1221, 1225-26, 93 L.Ed. 1528 (1949). We reverse and remand for further proceedings consistent with this opinion.
I. BACKGROUND
A complete recitation of the facts surrounding this case can be found in a prior appeal, Anthony v. Baker, 767 F.2d 657, 659-61 (10th Cir.1985) [hereinafter Anthony v. Baker I.] Here, we discuss only those facts relevant to this appeal. Plaintiff Robert Anthony filed this action against defendant Baker under 42 U.S.C. § 1983 for malicious prosecution. Baker, a deputy sheriff of the Sheriffs Office of El Paso County, Colorado, investigated a fire that occurred in the Springs Motor Inn on September 16, 1980. Anthony, the general manager of the inn at the time of the fire, was indicted, tried and acquitted for felony theft based on insurance fraud in connection with the fire.
Anthony’s malicious prosecution complaint challenges Baker’s motivation and conduct in nearly all phases of the investigation and resulting criminal prosecution against Anthony. Focusing on the grand jury and probable cause proceedings, Anthony’s complaint alleges the following: with Baker’s “procurance, advice, and assistance” and based partially on Baker’s false assertions, the grand jury began an investigation of the alleged arson; Baker presented “maliciously false, misleading and distorted evidence and testimony” to the grand jury, and these acts led to the *1397grand jury’s indictment of Anthony; after a judge dismissed the indictment, a prosecuting attorney filed a criminal information based on “false or created” information supplied by Baker; during the ensuing preliminary hearing on whether there was probable cause to bind Anthony over for trial, Baker testified and “again presented false, distorted, misleading and equivocal testimony”; Baker’s false testimony at the probable cause hearing and the transcript from the grand jury proceedings caused the court to find probable cause when probable cause would not have been found “but for the false, contrived and misleading evidence presented by Baker.”
Baker moved to dismiss Anthony’s complaint, or alternatively for partial summary judgment, on the grounds that Baker is absolutely immune from civil liability for his testimony before the state grand jury and the state trial judge at a preliminary hearing. The district court denied Baker’s motion because it found that, in Anthony v. Baker I, we had already ruled against Baker on the issues presented in Baker’s motions. The district court also noted that Baker presented the absolute immunity argument in a previous motion to dismiss filed in 1986. This motion was denied by a different district court judge on the grounds that, in Anthony v. Baker I, we ruled against Baker on the absolute immunity issue. In denying the present motion, the district court also determined that it was bound by the prior determinations of the issues presented in Baker’s motion under the “law of the case” doctrine.1
II. DISCUSSION
We must determine if Anthony v. Baker I decided whether Baker is entitled to absolute immunity for his testimony before a state grand jury and before a state trial judge at a preliminary hearing. If these issues were decided in Anthony v. Baker I, then the district court correctly determined it was bound by that decision as the law of the case. Eastern Cherokees v. United States, 225 U.S. 572, 582, 32 S.Ct. 707, 711, 56 L.Ed. 1212 (1912) (“When a case has been once decided by this court on appeal, and remanded to the circuit court, whatever was before this court, and disposed of by its decree, is considered as finally settled. The circuit court is bound by the decree as the law of the case.”) (citation omitted).
Whether Anthony v. Baker I settled the issues of absolute immunity for Baker’s grand jury and state preliminary hearing testimony is a question of law. Accordingly, we use a de novo standard of review. Fox v. Mazda Corp. of Am., 868 F.2d 1190, 1194 (10th Cir.1989).
A. IMMUNITY FOR DEPUTY SHERIFF BAKER’S GRAND JURY TESTIMONY
To resolve whether Anthony v. Baker I settled the issue of absolute immunity, we begin by examining the proceedings that led up to our earlier decision. In July, 1983 — one year after Anthony filed his suit and before the case had proceeded to trial — defendant Baker moved to dismiss or alternatively for partial summary judgment. Baker argued that the complaint against him should be dismissed because the action was based on his privileged testimony before the jury and grand jury. In October, 1984, the district court granted Baker’s motion, ruling that under Briscoe v. LaHue, 460 U.S. 325, 103 S.Ct. 1108, 75 L.Ed.2d 96 (1983), Baker’s testimony “before the grand jury or at plaintiff’s trial cannot form the basis of plaintiff's 1983 claim.”
The district court’s recognition of immunity for Baker’s trial and grand jury testimony did not dispose of Anthony’s § 1983 claim because Anthony’s complaint “al*1398leged other facts which [fell] outside the scope of immunity defined in Briscoe.” Accordingly, the district court allowed the case to proceed to trial. After the trial, the district court directed a verdict in favor of Baker, finding that there was insufficient evidence to allow recovery on Anthony’s § 1983 claim. Anthony appealed to this court, and we rendered a decision on that appeal in Anthony v. Baker I.
In Anthony v. Baker I, one of the issues we addressed was whether the district court correctly held in its pretrial ruling on summary judgment that Baker was protected by absolute immunity for his grand jury testimony and therefore that none of Baker’s grand jury testimony could form the basis of Anthony’s § 1983 claim. After reviewing our earlier decision, we conclude that Anthony v. Baker I decided only that the district court erred in granting Baker absolute immunity for his entire grand jury testimony. On his prior appeal to this Court, Anthony specifically argued that the district court erred in finding that, under Briscoe v. LaHue, Ba,ker’s testimony before the grand jury could not form the basis of Anthony’s § 1983 action for malicious prosecution. Anthony v. Baker I, 767 F.2d at 662. In response, Baker argued that he was entitled to immunity under Briscoe v. LaHue for his testimony during Anthony's criminal prosecution in state district court. Id.
After considering these arguments, we “concurr[ed] in Anthony’s contention that, contrary to the district court’s finding, Briscoe v. LaHue does not afford immunity for the testimony of the defendants before the Grand Jury.” Id. at 663. We did not decide that all grand jury witnesses lack absolute immunity, or even that Baker lacks immunity for each and every word of his grand jury testimony. Instead, without significant discussion, we reversed the district court’s holding affording blanket immunity for all statements at the grand jury proceeding, and we left it to the district court on remand to define the scope of immunity that attaches to grand jury testimony.
The district court erroneously dismissed Baker’s present summary judgment motion on law of the case grounds because Anthony v. Baker I did not determine the scope of immunity that attaches to Baker’s grand jury testimony. Anthony v. Baker I decided only that the district court erred in granting Baker absolute immunity for each and every statement uttered during the grand jury proceedings. Therefore, we must now proceed to define the scope of Baker’s immunity for his grand jury testimony.
In addressing questions of absolute immunity under § 1983, we take a functional approach, examining such factors as the recognition of immunity at common law, the risk of vexatious litigation, and the availability of safeguards other than civil litigation to help prevent abuses of authority. Burns v. Reed, — U.S. -, 111 S.Ct. 1934, 1941-44, 114 L.Ed.2d 547 (1991); Mitchell v. Forsyth, 472 U.S. 511, 521-22, 105 S.Ct. 2806, 2812-13, 86 L.Ed.2d 411 (1985). As we analyze this immunity question, we first must focus on the nature of the function Baker performed, rather than on Baker’s identity as a deputy sheriff. Forrester v. White, 484 U.S. 219, 230, 108 S.Ct. 538, 545, 98 L.Ed.2d 555 (1988). If we cannot conclude that Baker’s claim of absolute immunity would have been recognized at common law, we need not proceed beyond an examination of the immunity available at common law. Robinson v. Volkswagenwerk AG, 940 F.2d 1369, 1371 (10th Cir.1991) (if claim of absolute immunity was not recognized at common law, “we need proceed no further”), petition for cert. filed, (Oct. 30, 1991) (No. 91-715); see also Tower v. Glover, 467 U.S. 914, 922-23, 104 S.Ct. 2820, 2825-26, 81 L.Ed.2d 758 (1984); Burns, 111 S.Ct. at 1945 (Scalia, J., concurring in judgment in part and dissenting in part) (common law tradition of immunity is a necessary, but not sufficient, condition of absolute immunity in § 1983 actions).
In resolving questions of immunity, the common law distinguished between defamation actions and actions for malicious prosecution. In a defamation action, the plaintiff seeks to hold a witness “liable *1399only for the defamatory effect of his testimony, and in such an action he [the witness] enjoyed absolute immunity upon a threshold showing that the allegedly defamatory statements were relevant to the judicial proceeding.” White v. Frank, 855 F.2d 956, 959 (2d Cir.1988) (citing Briscoe v. LaHue, 460 U.S. 325, 330-32 & n. 11, 103 S.Ct. 1108, 1112-13 & n. 11, 75 L.Ed.2d 96 (1983)). In a malicious prosecution action, however, the plaintiff attempts to hold the complaining witness2 “liable for his role in initiating a baseless prosecution....” Id. “Complaining witnesses were not absolutely immune at common law.” Malley v. Briggs, 475 U.S. 335, 340, 106 S.Ct. 1092, 1095, 89 L.Ed.2d 271 (1986). Thus, in Mal-ley, the Supreme Court denied absolute immunity to a police officer who wrongfully initiated a criminal proceeding by applying for an arrest warrant. Id. “In 1871, the generally accepted rule was that one who procured the issuance of an arrest warrant by submitting a complaint could be held liable if the complaint was made maliciously and without probable cause.” Id. (citations omitted).
We have not discovered any pre-1871 malicious prosecution cases that grant absolute immunity to a complaining witness for testimony in a pre-trial proceeding. Even examining post-1871 cases as a reflection of the common law when § 1983 was enacted, we are not persuaded that a complaining witness would have been granted absolute immunity.
Unlike the plaintiff in Malley, Anthony does not allege that Baker initiated the prosecution by maliciously submitting a criminal complaint. Instead, Anthony’s complaint challenges both Baker’s motivation for his actions prior to the grand jury proceeding and Baker’s conduct during the grand jury proceeding.3
Because we are not convinced that the common law granted absolute immunity to a complaining witness who initiated — at least in part — a baseless prosecution by giving false testimony at a grand jury proceeding, we find the factual distinction between Malley and our case to be insignificant. In a case very similar to ours, the Second Circuit analyzed the immunity available to complaining witnesses at common law and concluded that “early cases ... [permitted] a plaintiff to recover in an action for malicious prosecution based in part upon the defendant’s appearance before the grand jury.” White, 855 F.2d at 960 (citing Dennis v. Ryan, 65 N.Y. 385 (1865); Fitzjohn v. Mackinder, 9 C.B. (N.S.) 506, 142 Eng.Rep. 199 (1861)).
The one asserting absolute immunity must demonstrate clear entitlement. Burns, 111 S.Ct. at 1944-45; Forrester, 484 U.S. at 230, 108 S.Ct. at 545; Robinson, 940 F.2d at 1370; Snell v. Tunnell, 920 F.2d 673, 676 (10th Cir.1990), cert. denied, — U.S. -, 111 S.Ct. 1622, 113 L.Ed.2d 719 (1991). Baker has failed to demonstrate that complaining witnesses were entitled to absolute immunity for their grand jury testimony at common law. On remand, the district court must resolve the disputed factual matter of whether Baker played the role of a complaining witness in the grand jury proceeding. If the district court determines that Baker acted as a complaining witness, then he is not entitled to absolute immunity for any of his grand jury testimony that is relevant to the manner in which he initiated or perpetuated the prosecution of Anthony.
Baker asserts that he is entitled to absolute immunity simply because he participated as a lay witness in the grand jury proceeding. As mentioned above, whether Baker was a complaining witness or a lay *1400witness is a factual question to be resolved by the district court. Baker urges this court to follow other circuits that have granted absolute immunity to witnesses testifying in a pre-trial proceeding.4
The Supreme Court recognized absolute immunity for witnesses who testify at trial. Briscoe v. LaHue, 460 U.S. 325, 103 S.Ct. 1108, 75 L.Ed.2d 96 (1983). In this Circuit, we extended Briscoe beyond the trial itself to judicial proceedings generally. See Tripati v. United States Immigration and Naturalization Serv., 784 F.2d 345, 348 (10th Cir.1986) (absolute immunity extends to probation officer who allegedly made false statements in pretrial bond report and presentence report), cert. denied, 484 U.S. 1028, 108 S.Ct. 755, 98 L.Ed.2d 767 (1988). In Tripati, we held that when “the challenged activities of a federal probation officer are intimately associated with the judicial phase of the criminal process, he or she is absolutely immune from a civil suit for damages.” Id. Other Circuits have relied on Tripati as support for granting absolute immunity to a witness testifying in a pretrial setting. See, e.g., Williams v. Hepting, 844 F.2d 138, 142-43 (3rd Cir.) (absolute immunity extends to witness who testifies at preliminary hearing), cert. denied, 488 U.S. 851, 109 S.Ct. 135, 102 L.Ed.2d 107 (1988); Holt v. Castaneda, 832 F.2d 123, 125-26 (9th Cir.1987) (witness who testifies in adversarial preliminary hearing is absolutely immune), cert. denied, 485 U.S. 979, 108 S.Ct. 1275, 99 L.Ed.2d 486 (1988); Daloia v. Rose, 849 F.2d 74, 76 (2d Cir.) (witness who testifies at pretrial suppression hearing is absolutely immune), cert. denied, 488 U.S. 898, 109 S.Ct. 242, 102 L.Ed.2d 231 (1988). We agree that when a plaintiff brings a § 1983 action to recover for the defamatory effects of perjured testimony, Tripati supports the extension of absolute immunity to witnesses for their grand jury testimony.
At common law, a lay witness testifying before the grand jury had absolute immunity. Kincaid v. Eberle, 712 F.2d 1023 (7th Cir.) (citing Lake v. King, 1 Wms. Saund. 131, 132, 85 Eng.Rep. 137, 139 (K.B. 1679); The King v. Skinner, 1 Lofft 55, 56, 98 Eng.Rep. 529, 530 (K.B. 1772); Kidder v. Parkhurst, 3 Allen 393, 396 (Mass.1862); Shultz v. Strauss, 127 Wis. 325, 328, 106 N.W. 1066, 1067 (1906)), cert. denied, 464 U.S. 1018, 104 S.Ct. 551, 78 L.Ed.2d 725 (1983). In addition to finding support in the common law, we find that the same policy concerns articulated by the Supreme Court in Briscoe v. LaHue support extending defamation immunity to a grand jury witness. If a witness could be liable for damages for defamatory statements made during a grand jury proceeding, then the witness might distort his or her testimony or might be reluctant to testify at all. This could “deprive the finder of fact of candid, objective, and undistorted testimony.” Briscoe, 460 U.S. at 333, 103 S.Ct. at 1114 (citation omitted).
Moreover, the grand jury proceeding is integral to the judicial phase of the criminal process. Although a grand jury proceeding offers fewer procedural protections— particularly regarding the opportunity to cross-examine, present rebuttal evidence, and the presence and representation of counsel — than a trial, the grand jury provides enough of the protections of a trial that grand jury witnesses should be absolutely immune. Furthermore, in Burns v. Reed, — U.S. -, 111 S.Ct. 1934, 114 L.Ed.2d 547 (1991), the Supreme Court found that a prosecutor is absolutely immune from liability for participating in a probable cause hearing. In making this determination, the Court did not examine *1401whether the procedural safeguards surrounding the probable cause hearing were sufficient to guard against unconstitutional conduct, and instead relied broadly on the safeguards built into the judicial system. Id. 111 S.Ct. at 1942. These safeguards also support our holding that a lay witness is entitled to absolute immunity at a grand jury proceeding.
We therefore conclude that if Baker did not function as a complaining witness, then any § 1983 claim for damages based on his grand jury testimony would essentially seek to hold Baker liable for the defamatory effect of his testimony. If Baker testified before the grand jury as a lay witness — and not as a complaining witness — then he is entitled to absolute immunity.
In sum, we hold that Baker, as a defendant in a § 1983 suit for malicious prosecution, should be denied absolute immunity for his grand jury testimony only if he is found to be a complaining witness and only if the testimony is relevant to the manner in which he initiated or perpetuated the prosecution of the plaintiff.
B. IMMUNITY FOR TESTIMONY AT STATE PRELIMINARY HEARING
The district court erred when it determined that Anthony v. Baker I decided whether Baker is entitled to absolute immunity for his testimony before a state trial judge during a preliminary hearing. That matter was neither argued on the appeal of Anthony v. Baker I, nor was it a part of the district court’s decision that preceded the appeal. Thus, we must now determine whether Baker should be given absolute immunity for his testimony before a state trial judge at a preliminary hearing. For the same reasons stated above, we hold that, in the context of a § 1983 claim for malicious prosecution, a complaining witness is not absolutely immune for testimony given in a pre-trial setting if that testimony is relevant to the manner in which the complaining witness initiated or perpetuated the prosecution.
Anthony alleges that the prosecuting authorities, “based upon the false or created information supplied by Baker, immediately filed a criminal information” after a judge dismissed the grand jury’s indictment. A preliminary hearing — the hearing now at issue — was held before a state trial judge to determine whether probable cause existed to bind Anthony over for trial.
Because Anthony’s § 1983 action for malicious prosecution is based in part on Anthony’s allegations concerning the probable cause hearing, we must determine whether Baker is entitled to absolute immunity for the testimony he gave at the preliminary hearing. Again, immunity hinges on whether Baker acted as a complaining witness or as a lay witness. Proceeding under a functional approach, we first examine immunity at common law. Burns, 111 S.Ct. at 1941-44. In an action for malicious prosecution, we find no evidence that a complaining witness was entitled to immunity for testimony at a preliminary hearing at common law. Therefore, we need proceed no further, see Robinson, 940 F.2d at 1371, and we conclude that a complaining witness is not entitled to absolute immunity in a malicious prosecution action for testimony given at a preliminary hearing.
Turning to the immunity of lay witnesses, we reach the opposite conclusion. First, we note that lay witnesses enjoyed absolute immunity for their testimony in judicial proceedings at common law.5 We also find that the policy concerns articulated for extending immunity to lay witnesses for their grand jury testimony apply to testimony at a preliminary hearing. The preliminary hearing is integral to the judicial process and contains the numerous safeguards that are built into the judicial system. Further, absolute immunity promotes uncensored testimony, which is es*1402sential to the finder of fact. Therefore, we conclude that a lay witness enjoys absolute immunity for testimony at a preliminary hearing.
Construing Anthony’s complaint in the light most favorable to him, we find that Anthony’s allegations concerning the grand jury proceeding and the probable cause hearing could provide a factual basis for the district court to conclude that Baker indeed was a complaining witness at both proceedings. We hold that, in the context of a § 1983 suit for malicious prosecution, a complaining witness is not absolutely immune for his testimony at either a grand jury proceeding or a preliminary hearing if that testimony is relevant to the manner in which the complaining witness initiated or perpetuated the prosecution. However, in the event that the defendant is not a complaining witness, we hold that he is absolutely immune for his pretrial testimony.
Whether Baker was a complaining witness in the grand jury proceeding and in the preliminary hearing are disputed factual matters that must be resolved by the district court. Therefore, we remand this case so that this matter may proceed in the district court in light of the principles we have established.
REVERSED and REMANDED.
. The law of the case doctrine is “a restriction self-imposed by the courts in the interest of judicial efficiency. It is a rule based on sound public policy that litigation should come to an end and is designed to bring about a quick resolution of disputes by preventing continued reargument of issues already decided.” Fox v. Mazda Corp. of America, 868 F.2d 1190, 1194 (10th Cir.1989) (citations omitted). The law of the case doctrine “encompasses a court’s explicit decisions, as well as those issues decided by necessary implication.” Williamsburg Wax Museum v. Historic Figures, Inc., 810 F.2d 243 (D.C.Cir.1987) (citations omitted).
. The term "complaining witness” describes the person (or persons) who actively instigated or encouraged the prosecution of the plaintiff. Proof of the defendant’s role in instituting the criminal prosecution of the plaintiff is an essential element of a malicious prosecution claim. W. Page Keeton et at, Prosser and Keeton on the Law of Torts § 119 (5th ed.1984); Lounder v. Jacobs, 119 Colo. 511, 205 P.2d 236 (1949).
. Among Anthony’s challenges to Baker’s conduct and motivation is the allegation that prior to the grand jury proceeding Baker deliberately created false evidence and distorted reports and failed to make a full and fair disclosure of his investigation for the purpose of misleading and misinforming the prosecutor and the grand jury.
. See, e.g., Strength v. Hubert, 854 F.2d 421 (11th Cir.1988); Little v. City of Seattle, 863 F.2d 681, 683 (9th Cir.1988); Williams v. Hepting, 844 F.2d 138 (3d Cir.), cert. denied, 488 U.S. 851, 109 S.Ct. 135, 102 L.Ed.2d 107 (1988); Holt v. Castaneda, 832 F.2d 123 (9th Cir.1987), cert. denied, 485 U.S. 979, 108 S.Ct. 1275, 99 L.Ed.2d 486 (1988); Macko v. Byron, 760 F.2d 95 (6th Cir.1985); Briggs v. Goodwin, 712 F.2d 1444 (D.C.Cir.1983), cert. denied, 464 U.S. 1040, 104 S.Ct. 704, 79 L.Ed.2d 169 (1984); Kincaid v. Eberle, 712 F.2d 1023 (7th Cir.), cert. denied, 464 U.S. 1018, 104 S.Ct. 551, 78 L.Ed.2d 725 (1983). We agree with the observation by the Second Circuit in White v. Frank, 855 F.2d 956, 961 (2d Cir.1988), that these decisions have not been careful to distinguish between the constitutional tort of giving false testimony and the constitutional tort of a complaining witness initiating a baseless prosecution.
. See McDavitt v. Boyer, 169 Ill. 475, 480, 48 N.E. 317 (1897); Laing v. Mitten, 185 Mass. 233, 235, 70 N.E. 128 (1904); Dodge v. Gilman, 122 Minn. 177, 142 N.W. 147 (1913); Liles v. Gaster, 42 Ohio St. 631, 635 (1885); Newell, Slander and Libel 544 (3d ed.1914); M. Schneiderman, Annotation, Libel and Slander: Application of Privilege Attending Statements Made in Course of Judicial Proceedings to Pretrial Deposition and Discovery Procedures, 23 A.L.R.3d 1172.