Legal experts predict case in Boston bomb scare will be difficult to prove

? Some legal experts say prosecutors will have a hard time proving that two men intended to cause a scare when they planted blinking electronic devices around Boston in a publicity stunt for a cartoon show.

They say the key difficulties prosecutors face are demonstrating that the men intended to cause fear, and that the devices, which depict a cartoon character, looked dangerous. The state must prove both to win felony convictions for placing a hoax device, the experts said.

“Their intent was to place these devices as part of an admittedly idiotic advertising campaign,” said defense attorney Edward P. Ryan Jr., a former president of the Massachusetts Bar Association. “Just because people got scared doesn’t mean there was intent.”

Peter Berdovsky, 27, and Sean Stevens, 28, were paid to place the devices to promote a television show on the Turner Broadcasting System subsidiary Cartoon Network, and even took videos documenting their work.

David White-Lief, the state bar’s president-elect and a Boston lawyer, said the lighted boxes probably do not meet the state statute’s definition of a hoax device, which must resemble an “infernal machine.” He interprets that description to mean something that looks like dynamite or a Molotov cocktail.

But the devices in Boston, which displayed a boxy-looking cartoon character giving the finger, “looked like toys,” White-Lief said.

More than three dozen electronic signs were placed in high-profile spots in Boston weeks before authorities responded Wednesday. Authorities shut down highways, bridges and river traffic while bomb squads checked out devices that turned out to be harmless. There was barely a stir in nine other cities across the country where similar devices were placed.

Berdovsky and Stevens pleaded not guilty Thursday and were released on $2,500 bail. They face up to five years in prison if convicted.

Turner Broadcasting, a unit of Time Warner Inc., apologized to Boston-area residents in full page newspaper ads Friday, with Turner’s chairman and chief executive officer expressing regret for “the confusion and inconvenience.”