settled that the finding of an indictment, fair upon its face, by a properly constituted grand jury, conclusively determines the existence of probable cause.” Barnes v. Wright, 449 F.3d 709, 716 (6th Cir. 2006) (internal citations and quotation marks omitted). A grand-jury witness has absolute immunity from § 1983 claims predicated on the witness’s testimony. Rehberg v. Paulk, 566 U.S. 356, 132 S.Ct. 1497, 1506, 182 L.Ed.2d 593 (2012). Absolute immunity “[cannot] be circumvented by claiming that a grand jury witness conspired to present false testimony or by using evidence of the witness’ testimony to support [a] § 1983 claim concerning the initiation or maintenance of a prosecution.” Id.; see also Briscoe v. LaHue, 460 U.S. 325, 326-27, 341-45, 103 S.Ct. 1108, 75 L.Ed.2d 96 (1983) (<HOLDING>). Absolute immunity does not protect “all
holding that the considerations underlying absolute prosecutorial immunity at common law dictate the same absolute immunity under  1983 recognizing that absolute immunity is immunity from charges of either constitutional or statutory violations holding that while a witness and prosecutor were protected by absolute immunity for their participation in judicial proceedings they were not entitled to absolute immunity on a  1983 claim that they conspired to present false testimony holding that prosecutors have absolute immunity holding that absolute immunity applies to claims of perjured testimony