Not only do they promote slander, they publish slander (libel).
*** w03 1/15 p. 23 “Zealous Kingdom Proclaimers” Joyfully Assemble ***
The talk “Guard Against Deception” showed that we wisely treat as poison the distortions, half-truths, and outright falsehoods propagated by apostates. (Colossians 2:8) Likewise, we must not deceive ourselves into thinking that we can indulge our sinful desires without dire consequences.
You consider me an apostate. Have you ever known me to lie about anything? Promote an outright false hood? Intentionally distort God's word? Tell a half-truth?
Now, on the other hand, have you ever known the Watchtower Society (a.k.a. Christian Congregation of Jehovah's Witnesses) to tell a half-truth? Intentionally distort God's word? Promote an outright falsehood?
If not, examine carefully the weight of evidence pointing to 609 BC as the time for the fall of Assyria under Nabopolassar and of 597 BC as the year when Jehoiachin (a.k.a. Jeconiah) was exiled to Babylon. Both of these years are more firmly established by secular sources than is 539 BC as the year of Babylon's fall. The WTS relies on secular history for the 539 date and rejects out of hand the proofs for these other years. If that isn't an outright half-truth, I don't know what is.
They go on to disfellowship any who press the issue too hard. That is organizational promotion of outright falsehood. They intentionally distort God's word to create a sense of authority for setting up Judicial Committees through which their nefarious organizational will is secretly carried out behind closed doors.
And they lie to you and tell you it is God's will.
And you believe them, despite any basis in Scripture for anything similar to a Judicial Committee and direct instruction to handle wrongdoing in a different way.