Sefer Chofetz Chaim Hilchis Rechilus chapter 1 halachos 4, 5

Halacha 4: It forbidden to be a tale bearer of news you heard or saw even if it is true. Not only if the party you are telling it to and the party you are talking about are on good terms with each other for sure that is terrible and the medrish in Vayikra Rabba 16:1 says there are 6 categories of people hated by Hashem and a seventh which is worse then all of them which is a person who speaks rechilus causing fights amongst loved ones. But even if they hate each other already it’s still rechilus to stoke the coals. There are many indications in chaza”l and poskim that rechilus even about the truth is still forbidden.

1. Moed Kattan 16a: Only a messenger of the court can tell the court if the person he was sent to summon to court cursed out the court but if he isn’t a messenger of the court he can’t tell the person spoken about even if true. This is learned from Moshe sending a messenger to summon Nadav and Avihu to his court and they cursed out Moshe. The messenger told what happened. The gemara says only because he was messenger of the court he was allowed to say if not it would be rechilus. We also see from here that there is rechilus even between 2 people who hate each other for Nadav and Avihu definitely hated Moshe as apparent from the verses dating all the way back to when they were in Egypt and Moshe Rabbeinu hated them because there is a mitzva to hate anyone who tries to convince and certainly if he is successful at convincing other to stay from Hashem’s Torah. No matter if it’s going idolatry or any other sin, all is going against Hashem which is a sin so one who convinces other to do that is hated by Hashem and there is a mitzvah for every Jew to hate that person whether he badly influences an individual or a group. Nadav and Avihu convinced hundreds to join them in rebellion against Moshe and the Torah given through Moshe therefore there was a mitzvah to hate them, still in all if the person telling the news wasn’t the messeof the court then he would not be able to tell Moshe what Nadav and Avihu told him.

2. Another proof that rechilus is even about the truth is from the gemara in Sanhedrin 29a which says that you can’t write down (announce) by name which judge said guilty or innocent because that would be rechilus.

3. In Bava Kamma 99b there was a case of a cow that was invalidly shechted the owner took the shochet to court to get his money back. Rav mistakenly said the cow was a treifa anyway so it would never have been kosher. Rav Kahana and Rav Asi poskined as a majority that the shochet has to pay for the mistake he made. They told the owner later that Rav had made a mistake. The gemara asked how Rav Kahana and Rav Asi could have told the owner of what happened isn’t that rechilus, even if it was true. The Rambam, Sma”g and Rabbeinu Yona all clearly poskin that rechilus is even on the truth as well.

Halacha 5: Itmakes no difference if on your own fruition you tell someone rechilus or if someone convinces you to divulge what the other guy did to him or said about him. Even if a rabbi or parent asks who did it or said it, as long as telling isn’t constructive, then it is rechilus, no matter how bad the news is, even if it is avak rechilus, it is nevertheless forbidden. Proof to this is because Doeg was held accountable for saying rechilus against Dovid and the city of Kohanim that protected him. King Shaul coaxed Doeg into telling him what happened besides the fact that he was and Doeg was afraid of the king still in all he was guilty of speaking rechilus. This is no different than someone trying to convince you to eat pig, you still would never do that and if did you get a sin so why woukd someone convincing you to divulge information which is rechilus be any different, it’s still forbidden and you should be held liable even if coerced for the sin you did.