The Case of the Nosy Neighbor

Charge: assault with a deadly weapon. Weapon: baseball bat. M.O.: aiming and swinging the baseball bat at Nosy Neighbor's head.

At D's jury trial the prosecution calls Nosy Neighbor as its first witness. Neighbor testifies to certain background facts, that D came up behind him and swung a baseball bat at him, but that he managed to duck just in time to avoid disaster. At this point the judge announces that it is time for the court's lunch recess. Upon reconvening at 2:30 p.m. the district attorney produces a 32-inch Louisville slugger, Roberto Clemente model baseball bat, has the clerk tag the bat for identification as People's Exhibit A, and tenders the bat in evidence as the weapon involved in the assault. Defendant objects. What ruling and why?