When he wouldn’t have sex with her she cried rape and he was thrown in prison without due process. It just doesn’t seem fair. (By the way Joseph later managed to save a whole population from starving anyway.)

 Genesis 39:6b-10

...Now Joseph was handsome in form and appearance.

And after a time his master's wife cast her eyes on Joseph and said, “Lie with me.”

But he refused and said to his master's wife, “Behold, because of me my master has no concern about anything in the house, and he has put everything that he has in my charge.

He is not greater in this house than I am, nor has he kept back anything from me except you, because you are his wife. How then can I do this great wickedness and sin against God?”

And as she spoke to Joseph day after day, he would not listen to her, to lie beside her or to be with her.

Bible Gateway link: Genesis 39 6-10 (ESV)