when did the ground rule double go into effect
Ground rule double In the early years of baseball, all batted balls that cleared the fence after a bounce in fair territory or on a fly were counted as home runs. The rule was changed by the American League prior to the 1930 season and subsequently by the National League on December 12, 1930. Notably, the pre-1930 rule includes most of Babe Ruth's career. Early baseball statistics do not differentiate between home runs that cleared the fence on a bounce compared to those that did not. However, most baseball historians believe that Ruth likely missed out on more home runs that did not count due to other differences in the rules in place during his career compared to the number of home runs he likely hit off bounces.[citation needed]
Double Jeopardy Clause Mistrials are generally not covered by the double jeopardy clause. If a judge dismisses the case or concludes the trial without deciding the facts in the defendant's favor (for example, by dismissing the case on procedural grounds), the case is a mistrial and may normally be retried. Furthermore, if a jury cannot reach a verdict, the judge may declare a mistrial and order a retrial as was addressed in United States v. Josef Perez, 22 U.S. 579 (1824). When the defendant moves for a mistrial, there is no bar to retrial, even if the prosecutor or judge caused the error that forms the basis of the motion. An exception exists, however, where the prosecutor or judge has acted in bad faith. In Oregon v. Kennedy, 456 U.S. 667 (1982), the Supreme Court held that "only where the governmental conduct in question is intended to 'goad' the defendant into moving for a mistrial may a defendant raise the bar of double jeopardy to a second trial after having succeeded in aborting the first on his own motion."