The statute allowing the government to appeal from some forms of trial court defeat in criminal cases, 18 U.S.C.A. § 3731, has a long and tangled history. In its 1970 opinion in United States v. Sisson 9ui the Supreme Court wrestled mightily with a difficult problem under the statute as it then stood, and invited Congress to amend "this awkward and ancient Act." Soon afterward the act was amended. It now provides in part that the government may appeal in a criminal case
from a decision, judgment, or order of a district court dismissing an indictment or information as to any one or more counts, except that no appeal shall lie where the double jeopardy clause of the United States Constitution prohibits further prosecution.
The Supreme Court has ruled that this provision was intended by Congress "to remove all statutory barriers to Government appeals and to allow appeals whenever the Constitution would permit." This interpretation has forced the Court to move the match to a new arena, putting aside statutory struggles to grapple with constitutional limitations of its own perception. Its first major effort came in three 1975 opinions that are described in detail in 15 Wright, Miller & Cooper, Federal Practice & Procedure: Jurisdiction § 3919. A brief summary of some of the major rules that had seemed to emerge from these decisions is set out below. This pref ace is followed by a detailed statement of several more recent decisions, drawn from the 1978 pocket part supplementing § 3919. It will be seen that the Court has not yet succeeded in articulating constitutional concepts that are clear enough to resolve many of the important questions.
Cooper, Edward H. "Government Appeals in Criminal Cases: The 1978 Decisions." Fed. Rules Decisions 81 (1979): 539-59.