Health, here are the relevant passages with the conditions from the Project Genesis Web Site:
5. Speaking Lashon Hara About a Heretic
The prohibition against speaking Lashon Hara applies when spoken about someone who is considered “amitecha” (of your people), namely in observance of Torah and mitzvot. However, regarding those who are recognizably “apikorsim” (heretics), it is a mitzvah (fulfillment of a positive commandment) to disparage and shame them, to their face and behind their back, for everything that one witnesses or hears about them.
The Torah states (Lev. 25:17 & Lev. 19:16) “One should not wrong his fellow” and “Do not act as a talebearer among your people,” but heretics do not fit under this category for they do not act as “your people.” Therefore, we follow the practice (as taught in Avot D’Rabbi Natan, a work from the Talmudic era), “those who hate you, L-rd, I will hate, and your rebellious ones I will dispute.”
An “apikorus” (heretic) is one who denies the laws and prophecies of Israel, whether the Written Law or Oral Law. Even if he says, “All the Torah is true with the exception of one Scriptural verse, kal v’chomer, g’zeira shava, or one grammatical detail,” he is included in this category. [“Kal v’chomer” and “g’zeira shava” are Talmudic terms for two of the logical principles from which we understand many laws.]
*Important note: there is a large in-between category not mentioned in this paragraph, namely those who do not observe – or even commit some sins – but without the malicious intent of heresy. Lashon Hara against someone in this middle category is forbidden. The purpose of these laws permitting speech against an actual heretic is not for a community to degenerate into nasty name-calling, but rather to protect itself against the influence of those who flagrantly do not care about the image they set for the community and even intentionally wish to destroy it.
6. Determining Whether Someone is Considered an Apikorus
[The permissibility to speak against an apikorus (heretic)] applies if one heard words of heresy directly from an individual. However, if he heard the heresy second hand, he is forbidden to speak against the person, whether in his presence or behind his back. Rather, he should suspect the person as an apikorus, and also warn others to stay away from him until the matter is clarified. Further, he should not believe in his heart that the information is true, according to the laws against accepting Lashon Hara discussed in chapter 6.
Verification is required when one hears that an ordinary person has spoken heresy, but if the person is a publicly confirmed heretic one may speak Lashon Hara about him as if he heard the heresy himself.
7. Speaking Lashon Hara about an Established Sinner
If a resident of a city is an established sinner, violating well-known laws, it is permissible to speak Lashon Hara about him.
(Here the Chafetz Chaim refers to his footnote enumerating the conditions that must be fulfilled to speak Lashon Hara in this case:
The speaker must have constructive intentions to encourage others to avoid the ways of evil, once they realize that such behavior is disparaged, and perhaps even to inspire the sinner himself to repent. He should not intend to benefit from exposing the other’s faults, nor should he speak out of hatred.
The speaker may not exaggerate about the subject’s behavior.
The speaker also should not act deceitfully, disparaging the person privately behind his back, yet flattering him in his presence; he should be comfortable speaking about him publicly. If, however he has a specific fear of retribution or swishes to avoid a public controversy, he may tell individuals privately. The speaker must be certain that his intentions are to prevent others from learning from the sinner’s evil ways.)
Who is classified as an established sinner? One who is designated as such by the town elders, based on which there can be no doubt, due to constant, numerous reports regarding his adulterous acts or other transgressions that are of the type that everyone knows they are forbidden.
If, however, there were only a rumor about him, it would be forbidden on that basis to speak against him, Heaven forbid. Even to decide in one’s heart is forbidden, as we discussed previously in chapter 7.
8. Speaking Lashon Hara about Ba’alei Machloket
Regarding the permissibility to speak Lashon Hara about those who are “ba’alei machloket” (people who are either polemic by nature or regularly engage in prolonged public disputes), it applies in certain circumstances. If a dispute is rooted in a deception [which violates Torah law] on the part of one side [thereby called a “ba’al machloket”], and if exposure of the deception will reveal that his position violates the halacha and will, therefore, more quickly resolve the dispute, then Lashon Hara is permitted. If the dispute will not be resolved as a result of the Lashon Hara, it is forbidden.
In addition, the following conditions are required:
The individual or group on the deceiving side are established “ba’alei machloket,” not merely rumored to be such, but rather verified by the speaker himself.
The speaker must have pure intentions, as discussed above. He must speak out of desire to resolve the quarrel, not out of hatred.
If silencing the dispute can be done by means other than speaking about the dishonest individual or group, such as direct rebuke or the like, it is forbidden to resort to Lashon Hara. (Unless he is afraid to rebuke them, for when they learn that he does not agree with them, they will negate what he tells others, and he will have no way to further address the situation.)
Speaking against ba’alei machloket requires careful consideration, and one should not rush to decide that one side is wrong and conclude that they are the ba’alei machloket. Rather, he must deliberate thoroughly according to the guidelines of Torah law. And if one cannot clarify which of the parties is correct, it is better not to get involved. [end of passages]
You still have not answered my questions. Do you hate smokers and people who cheat on their taxes?