Source: https://www.justice.gov/jm/criminal-resource-manual-629-discovery-alibi-witnesses-fed-r-crim-p-121
Timestamp: 2019-04-21 00:37:43+00:00

Document:
Rule 12.1(a) of the Federal Rules of Criminal Procedure permits the government, on written demand, to discover before trial a defendant's alibi and alibi witnesses. However, in exchange for such discovery, the government must disclose to the defense the names and addresses of the witnesses upon whom it intends to rely to establish the defendant's presence at the scene of the offense, and any other witnesses to be relied on to rebut testimony by the alibi witnesses. Rule 12.1(b). The parties are under a continuing duty to notify each other of additional witnesses who should have been included among those originally disclosed. Rule 12.1(c). Because the Rule provides for mutuality of discovery, it should satisfy the constitutional requirements of the Fifth Amendment. See Williams v. Florida, 399 U.S. 78 (1970); Wardius v. Oregon, 412 U.S. 470 (1973).
Non-compliance by either party may result in the exclusion of the testimony of the undisclosed witness (other than the defendant). Rule 12.1(d). See generally Taylor v. Illinois, 484 U.S. 400 (1988), on exclusion as a remedy for discovery abuses; United States v. Reed, 40 F.3d 1069 (10th Cir. 1994), cert. denied, 115 S. Ct. 1387 (1995). A finding of bad faith is not a prerequisite to exclusion, but it is an important factor in determining whether exclusion is appropriate. United States v. Johnson, 970 F.2d 907 (D.C. Cir. 1992). Courts may be reluctant to exclude reliable alibi testimony as a sanction for negligent conduct where the prejudice to the government would be minimal. See Bowling v. Vose, 3 F.3d 559 (1st Cir. 1993), cert. denied, 510 U.S. 1185 (1994).
Non-compliance may be excused for good cause shown. Rule 12.1(e). The need to protect the safety of a government witness has been held to constitute good cause for nondisclosure. See United States v. Wills, 88 F.3d 704 (9th Cir.), cert. denied, 117 S. Ct. 499 (1996).
If a defendant withdraws an alibi defense, the fact that he once intended to assert it may not be used against him in any civil or criminal proceeding. Rule 12.1(f).

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