Order 66 remains one of the most important events in the Star Wars timeline, and it revolves around a tiny piece of technology – the inhibitor chip implanted in every clone trooper’s brain. Ostensibly designed to instill unyielding loyalty in the Republic’s soldiers during the Clone Wars, the chip had a secret, sinister second purpose – to trigger the Jedi Purge, once the time was right. That moment has played out numerous times in numerous movies, shows, comics and video games, but how does the inhibitor chip itself actually work?
The clone inhibitor chips, also referred to in canon as behavioral modification biochips, are microscopic devises built of carefully engineered organic cells. Clones receive their chips relatively early in the growth process, allowing for them to be embedded incredibly deep in the brain. In Star Wars: The Clone Wars, it takes a particularly high-level brain scan to detect the chip at all, and its organic composition theoretically makes it much less prone to malfunction.
Inhibitor chips of this kind were not uncommon in Kaminoan cloning, and the clone biochips were initially meant to ensure clones would stay loyal to the Republic in the event a Jedi commander went rogue. Similarly, the chips were also designed to further alter their code, making them less independent, presumably by blocking (or inhibiting) the part of the brain that gave those thoughts and commands. However, Darth Sidious also used the device as a backdoor to program in obedience to Order 66. The order was a specific trigger, which compelled all affected clones to hunt and kill Jedi above all other priorities. Any hesitation in this mission was frozen by the inhibitor chip, and clones would even turn on their own brothers if they detected some sort of malfunction in the chip’s control. Star Wars: The Bad Batch showed how this affected their personalities too: some clones acted more menacingly, while many were stripped of any semblance of their old personality completely.
In that way, the tragedy of Order 66 is really twofold. There is of course the tragedy of all the Jedi who were killed, but there is also the tragedy of the clones themselves being robbed of their humanity. Yes, they were always under strict programming to follow orders, but they retained a level of autonomy and individuality in spite of that. That allowed them to develop real relationships with their comrades and the Jedi who led them. But when the chips were activated, all those old loyalties were effectively erased in an instant.
Another curious piece of information about the function of the behavior modification biochips is that, once they were activated, clone troopers became aware of Emperor Palpatine’s secret identity. There are documented instanced of clones referring to Sidious as “my lord” in the wake of Order 66 being executed, suggesting that something in the chips’ programming revealed his true nature. It’s an oddly risky choice on behalf of Palpatine, but it didn’t have much impact on his overall control of the Star Wars universe.
