## Facts

- The Bureau of Internal Revenue investigated certain New York firms for suspected tax violations in the late 1940s.
- An attorney for the firms allegedly sought help from Henry Grunewald, a Washington intermediary, to prevent criminal prosecution in exchange for substantial fees.
- The government alleged Grunewald used connections with senior revenue officials, including Max Halperin and Daniel Bolich, to obtain “no prosecution” rulings for the firms in 1948–49 through corrupt means.
- After the rulings, the participants allegedly engaged in secrecy and later acts to hide the wrongdoing, including false statements and efforts to mislead investigators once congressional and grand-jury inquiries began.
- A federal grand jury returned an indictment on October 25, 1954 charging all three with conspiracy to defraud the United States under 18 U.S.C. § 371; Halperin was also charged with corruptly endeavoring to influence grand-jury witnesses under 18 U.S.C. § 1503.
- The district court convicted all petitioners on the conspiracy count and convicted Halperin on the obstruction counts; the court of appeals affirmed.
- At trial, the prosecution cross-examined Halperin about his prior invocation of the Fifth Amendment before a grand jury in a related matter.

## Issues

1. Whether post-objective acts of concealment can be treated as overt acts in furtherance of the original conspiracy to satisfy the statute of limitations for an 18 U.S.C. § 371 charge.
2. Whether the jury instructions properly limited the jury to a timely conspiracy theory (either an objective continuing into the limitations period or an expressly agreed concealment phase as part of the original plan).
3. Whether the prosecution may use a defendant’s prior invocation of the Fifth Amendment privilege before a grand jury to impeach the defendant at trial.

## Decision

- The Supreme Court reversed the convictions and remanded for a new trial.
- The Court held that, if the conspiracy’s central objective was obtaining the “no prosecution” rulings in 1948–49, the prosecution was time-barred because the record did not show an express agreement to continue concealing as part of the original conspiracy.
- The Court held the jury charge was inadequate because it permitted conviction even if the jury found the conspiracy’s central objective was completed by 1949 and later concealment occurred only to avoid detection and punishment.
- The Court held it was improper to use Halperin’s prior assertion of the Fifth Amendment privilege before the grand jury to attack his credibility, contributing to the need for a new trial.

## Legal Principles

- To satisfy the conspiracy statute of limitations, the government must prove the conspiracy existed within the limitations period and that at least one overt act in furtherance of the conspiracy occurred within that period.
- Acts of concealment that occur after the central objectives of a conspiracy have been achieved, undertaken only to cover up and avoid punishment, do not extend the life of the conspiracy for limitations purposes.
- A separate, continuing agreement to conceal cannot be implied solely from secrecy, continued secrecy after completion, or later attempts to cover up when the scheme comes to light; an agreed concealment phase must be proven as part of the original plan or shown to further attainment of the scheme’s central objectives.
- When the government relies on an extended-objective theory to avoid the statute of limitations, the jury must be instructed so it cannot convict without finding that extended objective was part of the original conspiratorial agreement.
- A defendant’s prior invocation of the Fifth Amendment privilege against self-incrimination may not be used at trial as impeachment or as a basis to suggest guilt, because doing so penalizes the exercise of the privilege.

## Conclusion

The Court set limits on extending conspiracy liability past completion of the scheme’s main objective, holding that post-completion concealment does not toll the limitations period absent proof that concealment was part of the original agreement, and it barred prosecutorial use of a defendant’s prior Fifth Amendment invocation to attack credibility at trial.


Grunewald v. United States, 353 U.S. 391 (1957)