Answer:
Polygraph tests are used to determine whether someone is lying or not, and display the physical signs someone is showing when they speak to be interpreted. Polygraphs measure things like heartbeat, breathing rate, and electrical conductivity of the skin, which are signs that get more and more severe when someone tells major lies or lies a lot. Polygraph tests are pretty unreliable because everyone shows different reactions to speaking depending on how anxious they are or any other medical condition, which could falsely incriminate them, but I think it is still important to determine the signs someone displays to use as a datapoint later on in the trial. For those reasons, they should still be used but shouldn't be relied on as heavily.
Explanation:
