A inter galactic civilization is at war with a less advanced civilization, but one with a highly unusual number of super individual. Not only was the invasion of their system unsuccessful, but soon after an infiltration unit managed to steal several ships and FTL technology. The galactic civilization is now reorganizing its security to prevent a second breach based on the last successful breach: they know they have to defend against 3 types of super-powered infiltrators.

  1. Psychics. Capable of causing hallucinations that make whoever sees/hear them (or someone accompanying them) perceive them as someone who belongs where ever they are. The effects works through cameras but has a limited range of around a mile. (Give or take a little bit depending on the power of the psychic.) This doesn't work on non sentient creatures. Also able to read minds.

  2. Shape shifters: Capable of changing their shape and DNA, unable to change their mass.

  3. Illusionists: capable of manipulating light to make illusions or turn things invisible.

What measure could an advanced civilization take to prevent more infiltrations?

  • $\begingroup$ Why, issue an imperial directive to establish the Transportation Security Administration. That will surely prevent any inn filtrator from boarding any star base. $\endgroup$ – AlexP May 15 at 14:37
  • 2
    $\begingroup$ Presumably psychics don't work on computers and light manipulating illusionists don't affect other frequencies and sensors (IR, UV, RF, x-ray, sound and vibration sensors, chemical sensors), so extensive use of computer controlled multi-sensor monitoring systems and body scanners at checkpoints will make life difficult for these infiltrators. $\endgroup$ – GrumpyYoungMan May 15 at 17:50
  • $\begingroup$ When you say "sentient"...... are you counting dogs? It seems to be a remarkably difficult to pin-down term as there are so many definitions and gradations. $\endgroup$ – A Rogue Ant. May 15 at 22:37
  • $\begingroup$ Closer to human level intelligence then sense of self. $\endgroup$ – Bryan McClure May 16 at 3:06

It looks like your security forces need to implement some basic Master/Stranger protocols which are designed to prevent security breaches from exactly these sorts of infiltrators. It should be noted however, that no individual security measure solves all your problems. Any proper security system involves multiple redundeant layered defenses to provide different levels of "trust".

Here are some suggestions:

  • Normalize bio-recognition systems. Every time you board a starship, station, or even go though a security door, you've got to go through some scanner(s) that could check your iris, fingerprint, body shape, bone density, etc. These scanners are completely automated and while DNA-replicating shapeshifters can maybe fool them, this makes it more difficult for the psychics and illusionists (also, fingerprints are not a function of DNA! A shapeshifter would need to actually lift the target's fingerprints off a surface and use that pattern to guide their shape-shifting/make a prosthetic fingertip.)

  • Implement habit/person recognition AI via cameras. Instead of searching for things like fingerprints or facial scans, create an AI that identifies people by their habits. For example, gait recognition is already in use today and is both extremely easy to track and basically impossible to use to imitate someone else. Even an exact DNA shapeshifter probably wouldn't learn to walk the way the person they're imitating walks exactly. To do so, they'd need to copy someone's deep muscle memory, which I can imagine would be difficult for a psychic.

  • Basic anti-invisibility sensors. Dealing with invisible infiltrators isn't too difficult. Simply make sure that all critical doors and access ways are always "airlocks" that is a system of doors where two can't be open at the same time. Even better, make the airlock so small that only one person can physically fit into the space at a time so that invisibility infiltrators can't sneak in alongside someone authorized. Additionally, you can use sensors that don't rely on visible light like IR cameras to pick up thermal signatures or pressure plates to pick up the mass people stepping on them.

  • The tank. If someone is suspected of being an infiltrator, they need to go into solitary lockup for 24-72 hours. All workers in security critical environments are taught this, and maybe even paid overtime for time that they spend in "the tank". This encourages people to be suspicious and report other people without creating an overtly hostile environment. While the people suspected of being an infiltrator are in the tank, they go through a variety of personality tests and are under close observation by specialists. Unbeknownst to the specialists who are doing the observing, they are also under watch by remote specialists so that if a psychic who's in the tank attempts to mind-magic the observers behind the mirrored glass, the remote observers notice.

  • Passwords, passwords, passwords. Anyone working in a security critical area is going to need to become good at remembering access codes and challenge-response codes that change often. These can be used whenever by whomever, for example, if specialist Jane says, "Security code Omega-four-seventeen-november-rabbit" and her coworker doesn't immediately reply with "Zulu-five-hotel-hotel-niner" (or whatever the proper daily code is), then Jane is authorized and obligated to immediately subdue the coworker and put them into the tank for screening. Note that these codes are changed often so that even if a psychic infiltrator gains access to someone, the codes they gain would only work for a short time if they're not already expired.

  • Compartmentalization. This is already a standard procedure used for sensitive information here on Earth today. Essentially, it means that nobody knows everything. Information is "need-to-know" and even if someone is completely compromised by a shapeshifter/psychic, then the amount of damage they can do with that information is limited. People who, by necessity, need to know a lot would be placed under more extreme security procedures and protocols.

  • Anti-psychic measures. Even if there are no technological countermeasures against psychic powers, I assume it would be possible to train oneself to become resistant to hallucinations/mind magic. Even for grunts it should be easy enough to train them to press an emergency signal button if they think they're under the effect of some sort of mental effect. Similarly, memory manipulating drugs could be used to prevent mind reading. Scientists who retire might be forced to take an amnesia drug that wipes out details of what they worked on or more esoteric techniques like hypnosis could be used to render people incapable of remembering things they shouldn't.





  1. Psychics can't mess with them.

  2. Shapeshifters cant fool them. The shape is all visual but robots rely less on sight and more on other senses, like body composition as measured by electrical conductance and mass as measured by muon backscatter.

  3. #2 applies to illusionists as well. Apparent objects which do not displace gas on moving will immediately be recognized as such. Objects with no mass are no objects.

If you robots are all the sexy type and are occupied making liquor ads, you could use trained dogs for #2 and #3 as well. Dogs will sniff out the truth. Psychics can mess with dogs a little bit which could be good for your story. Best would be a team of 2 types of your supers working together to get past dogs and robots.

But not cyborg dogs!


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