Inviting Jury to Speculate on Uncommitted Crimes In Closing Argument

In Darden v. State, 629 S.W.2d 46 (Tex. Crim. App. 1982), the prosecutor invited the jury to speculate on uncommitted, extraneous offenses: The prosecution for aggravated robbery, the evidence presented at trial established that the appellant shot a convenience store clerk in the course of a robbery and the body was discovered a half hour later by Leath. In closing argument, the prosecutor asked the jury: Suppose that Leath would have had the bad fortune to walk in there thirty minutes earlier when he was buying his Dr. Pepper ? Don't you suppose he would have gunned down Leath ? Id. at 52. The prosecutor in Darden injected new, harmful facts into the trial and invite the jury to speculate on uncommitted, extraneous offenses.