Sylvia Paull writes an excellent commentary on the responsibility and accountability of the publicist. 

While the case in point is about political PR, the lesson is universal.  If you're in public relations, and your client gives you falsehoods to promote, and you know it, you're just as guilty of lying.  No matter how many books you sell later to rationalize your behavior.

Want to know why people have come to mistrust the PR "professional?"  Read Sylvia's commentary.