Abe was Japan’s best-known politician and longest-serving prime minister, but security was comparatively light as he delivered a stump speech on a street in the western region.
Local police in the area have already acknowledged “undeniable” flaws in security for the former leader.
Bodyguards could have saved Abe by shielding him or pulled him from the line of fire in the 2.5 seconds between a missed first shot and the second, fatal round of gunfire, eight security experts who reviewed the footage have told Reuters.
Japanese officials, including Prime Minister Fumio Kishida, have acknowledged flaws in the security around Abe’s appearance at the election campaign event.
The National Police Agency previously told Reuters the killing had been the result of police failing to fulfil their responsibility, adding that it had set up a team to review security and protection measures and evolve preventive steps.