Futuristic Science Fiction Book - Realistic possible future [s]

[Js]

Story where a lie detector machine is invented by inventor X. Knowing that the lie dector machine was inevitable, 2 people almost never lie, and after the machine is in widespread use, one becomes the president(?) (The other person is his wife?) The president builds and sells lie detector machines, which then become a part of daily civil life. He programs the machines to allow himself the ability to lie. I think he is able to lie when thinking strongly about a poem that has the line Oh captain, my captain, ... The society is otherwise our current society, no super powers or potions, etc.

[Tab]

The Truth Machine , is a guess

[Andria]

And a good guess, too. :)

[Js]

It is the Truth Machine. Thank You, and I'm sorry I didn't reply to this earlier.