Liar
A liar, swindler, deceiver, angler was someone who was reputable for telling lies. 

In 2268, the crew of the  was forced to once again deal with "Harry" Mudd, a con artist that they had had previous dealings with. These dealings ultimately provided an opportunity to confuse an android, Norman, who had been posing as a member of the ship's crew. Describing Mudd to Norman, James T. Kirk stated, "Everything Harry tells you is a lie. Remember that. Everything Harry tells you is a lie." Mudd then told the android, "Listen to this carefully, Norman. I am lying," trapping the android with a type of paradox and eventually leading to a breakdown due to a flood of illogic. ()

Garth of Izar once said that Marta was "the greatest liar I have ever met," when she claimed to have written a verse from a  by William Shakespeare. ()

Vash once told Jean-Luc Picard that the problem with being a well-known liar was that nobody believed her even when she told the truth. ()

In 2368, when Helena Rozhenko told Worf that his son Alexander did not always tell the truth, Worf asked if his son was a liar. She replied that he was a boy and boys sometimes took the wrong path. ()

On the planet , Q was known as the "God of Lies". ()

Agnes Jurati told Jean-Luc Picard that she was a terrible liar, meaning she was not good at lying. ()

See also 
 Quack
 Snake oil salesman

External link 
 
Illegal occupations