What is the published collection that contains the decisions of the United States District Courts?

The published collection that contains the decisions of the United States District Courts is known as the Federal Supplement. This series includes the opinions published from the district courts, making it a crucial resource for legal researchers seeking to understand lower court rulings on federal statutes and regulations. Each volume is organized by year and represents the formal documentation of case law developed at the district court level.

The Federal Reporter, on the other hand, primarily publishes decisions from the United States Courts of Appeals, which is distinct from the decisions at the district court level. The Federal Rules Decisions contains interpretations of the Federal Rules of Civil Procedure, but it does not compile the actual case opinions. The United States Code is a consolidation of federal statutory law, providing the text of enacted statutes rather than containing judicial opinions. Thus, the Federal Supplement is specifically dedicated to the case law from United States District Courts, making it the correct answer.