Daily Business Ethics Halacha #16

Misleading and deceptive advertising is prohibited in Halacha under the interdict against creating a flase impression -geneivat da'at.

There is a dispute among Talmudic decisors as to where we the principle of geneivat da'at is derived from the Torah.  R. Jonah b Anraham Gerondi in his Shaarei Teshuva (Spain, 1200-1264) says it is derived from the prohbition of lying.  R. Yom Tov Ishbili, the Ritva, (Spain, 1250-1330) contends that it falls under the prohibition against theft. 

What would be the practical difference between deriving it form lying or from theft?

Rabbi Levine does not get into this question.  I have not studied the topic thoroughly myself, but I would guess that the difference would be the accountability that someone guilty of geneivat da'at would be held to.  accept in certain cases of purgery, in Jewish law it is hard to hold someone accountable in court for an mere words that were not accompanied by an action.  If however it constitutes theft, then perhaps a person can be judged as if he stole property with his hands.