Opinion ID: 1185757
Heading Depth: 1
Heading Rank: 4

Heading: The Model Explosive Device

Text: (8) Defendant complains that because the People failed to establish a foundation that a model bomb prepared by an expert witness was substantially and approximately a model of the type which was exploded in the house trailer, the court committed prejudicial error in receiving the model in evidence to aid the jurors in understanding the expert's testimony. The model illustrated how it would be possible by applying pressure to a triggering device to cause an electrical circuit to close and a dynamite cap to detonate, in turn detonating a charge of dynamite. Neither a cap nor dynamite was used in the model, and an electric lamp was used to demonstrate the closing of the electrical circuit when force was applied to the triggering device. The witness testified that he had received training in homemade explosive devices, that his model was illustrative of one of several types of explosive devices which could be activated by the movement of an element of the device known as the trigger, that the trigger could be one of several mechanisms (a mercury switch, a metal washer through which a piece of metal could be inserted and suspended, a mousetrap or clothespin with a piece of cardboard inserted between wired contact points), and that the model he had prepared and the triggering device he had used were not intended to illustrate the mechanism which was actually used to detonate the charge of dynamite in the instant case. The triggering device used in the model was a clothespin, the wired prongs of which were held apart by cardboard. When the cardboard was pulled from between the prongs the wires came into contact, closing the circuit and causing the flow of electricity. The device could be cocked by attaching the cardboard to a string or wire, the other end of which was attached to a door. When the door was opened the cardboard would be pulled from between the prongs, triggering the device. Defendant objected to the use of a clothespin with the model as there was evidence that defendant had borrowed a clothespin from Priscilla's daughter on the day before the explosion. The court, in overruling the motion outside the presence of the jury, required the prosecution to explain through its expert witness that a clothespin was only one of a number of devices which might have been used to trigger a bomb. The witness further testified that he did not know what device was actually used and that he had used a clothespin in his model only because it was easily available to him. [12] Defendant's contentions of undue prejudice by the prosecution's utilization of the model is not supported by the record. The role of the clothespin was not emphasized, and the court carefully kept the use of the model and implications therefrom in proper perspective. There was no abuse of discretion in permitting the use of the model under the conditions imposed by the court. (See People v. Kynette (1940) 15 Cal.2d 731 [104 P.2d 794]; Church v. Headrick & Brown (1950) 101 Cal. App.2d 396, 415 [225 P.2d 558].) Defendant's further contention that the prosecution failed to establish a proper foundation for admission of the model is not only without merit, [13] but also cannot be urged by defendant for the first time on this appeal. (Evid. Code, § 353; People v. Williams (1970) 11 Cal. App.3d 970, 979 [90 Cal. Rptr. 292].)