Technological tea-leaf readings are all they are. Without getting too personal I will simply say that I have personal experience passing polygraphs while bold-faced lying on nearly half a dozen occasions, after having previously failed them nearly the same number of times while absolutely telling the truth. They do not detect "deception", they measure the physiological fluctuations that an individual undergoes when attempting to answer an un-answerable question (known as a "control" question), and use those results as baseline assumptions of what deceptive results resemble. Anyone can pass a polygraph with enough psychological preparation and a strong enough "screw you, prove me wrong" type attitude.
They are not admissible in court because they aren't scientific; they are tools of technological tyranny used to intimidate people into divulging information that the interrogator, or "tester" if you want to be naive, could never have otherwise known. I recommend researching the information at https://antipolygraph.org/ if anyone here wants to educate themselves regarding the fraud that these "tests" actually are.
There is no higher end than the total liberation of the human being: mind, body and spirit.