What are the reasons for the secrecy of a grand jury?

1 Reasons for grand jury secrecy are stated in United States v. Proctor and Gamble, 356 U.S. 677, 681-682 n.6, 78 S.Ct. 983, 985-986 n.6, 2 L.Ed.2d 1077 (1958), quoting United States v. Rose, 215 F.2d 617, 628-629 (3rd Cir. 1954): "(1) To prevent the escape of those whose indictment may be contemplated; (2) to insure the utmost freedom to the grand jury in its deliberations, and to prevent persons subject to indictment or their friends from importuning the grand jurors; (3) to prevent subornation of perjury or tampering with the witnesses who may testify before grand jury and later appear at the trial of those indicted by it; (4) to encourage free and untrammeled disclosures by persons who have information with respect to the commission of crimes; (5) to protect innocent accused who is exonerated from disclosure of the fact that he has been under investigation, and from the expense of standing trial where there was no probability of guilt."