Save "When should we speak Lashon Hara?

The Parameter's of Lashon Hara Le'toelet
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When should we speak Lashon Hara? The Parameter's of Lashon Hara Le'toelet
Lashon Hara Le'toelet: Constructive Purposeful Lashon Hara

(טז) לֹא־תֵלֵ֤ךְ רָכִיל֙ בְּעַמֶּ֔יךָ לֹ֥א תַעֲמֹ֖ד עַל־דַּ֣ם רֵעֶ֑ךָ אֲנִ֖י ה'.

(16) Do not deal basely with your countrymen. Do not profit by the blood of your fellow: I am the LORD.

What idea links these two laws together in this Passuk?

(טו) וְיוֹחָנָ֣ן בֶּן־קָרֵ֡חַ אָמַ֣ר אֶל־גְּדַלְיָהוּ֩ בַסֵּ֨תֶר בַּמִּצְפָּ֜ה לֵאמֹ֗ר אֵ֤לְכָה נָּא֙ וְאַכֶּה֙ אֶת־יִשְׁמָעֵ֣אל בֶּן־נְתַנְיָ֔ה וְאִ֖ישׁ לֹ֣א יֵדָ֑ע לָ֧מָּה יַכֶּ֣כָּה נֶּ֗פֶשׁ וְנָפֹ֙צוּ֙ כָּל־יְהוּדָ֔ה הַנִּקְבָּצִ֣ים אֵלֶ֔יךָ וְאָבְדָ֖ה שְׁאֵרִ֥ית יְהוּדָֽה׃ (טז) וַיֹּ֨אמֶר גְּדַלְיָ֤הוּ בֶן־אֲחִיקָם֙ אֶל־יוֹחָנָ֣ן בֶּן־קָרֵ֔חַ אַֽל־תעש [תַּעֲשֵׂ֖ה] אֶת־הַדָּבָ֣ר הַזֶּ֑ה כִּֽי־שֶׁ֛קֶר אַתָּ֥ה דֹבֵ֖ר אֶל־יִשְׁמָעֵֽאל׃ (ס)

(15) Johanan son of Kareah also said secretly to Gedaliah at Mizpah, “Let me go and strike down Ishmael son of Nethaniah before anyone knows about it; otherwise he will kill you, and all the Judeans who have gathered about you will be dispersed, and the remnant of Judah will perish!” (16) But Gedaliah son of Ahikam answered Johanan son of Kareah, “Do not do such a thing: what you are saying about Ishmael is not true!”

וכי גדליה הרגן והלא ישמעאל הרגן אלא מתוך שהיה לו לחוש לעצת.

Who does the Gemara seem to blaming for Gedaliah's death? Wasn't Gedalyeh doing the right thing in not listening to Lashon Hara?

לאחר פטירתו של ר' מאיר אמר להם רבי יהודה לתלמידיו אל יכנסו תלמידי רבי מאיר לכאן מפני שקנתרנים הם ולא ללמוד תורה הם באים אלא לקפחני בהלכות הם באים

How was Rebbi Yehuda able to speak like that about Rebbi Meir's Students? Wasn't it Lashon Hara?

(כה) דְּאָגָ֣ה בְלֶב־אִ֣ישׁ יַשְׁחֶ֑נָּה וְדָבָ֖ר ט֣וֹב יְשַׂמְּחֶֽנָּה׃
(25) If there is anxiety in a man’s mind let him quash it, And turn it into joy with a good word.

(משלי יב, כה) דאגה בלב איש ישחנה רבי אמי ורבי אסי חד אמר ישחנה מדעתו וחד אמר ישיחנה לאחרים.

Might these sources leave the door open for a Heter to vent to your best friend/spouse?

Sefer Chassdim of Rebbe Yehuda Hachasid:
In 2 situations one may listen to Lashon Hara:
1)When your intention is to calm down the speaker,
2) If you will save him from the Issur of speaking to others.
In your heart, you must not completely accept the Lashon Hara.
Since your intention is pure, this is not considered Lashon Hara,
Chafetz Chayim Hilchot Lashon Hara 8:10, 10:14
Rav Aviner: Ofcourse, this is only a Bdieved Heter. Ideally, a person should try to get rid of the negative feelings without the need to speak about others negatively.
(ט) זָכ֕וֹר אֵ֧ת אֲשֶׁר־עָשָׂ֛ה ה' אֱלֹקֶ֖יךָ לְמִרְיָ֑ם בַּדֶּ֖רֶךְ בְּצֵאתְכֶ֥ם מִמִּצְרָֽיִם׃ (ס)
(9) Remember what the LORD your God did to Miriam on the journey after you left Egypt.
(א) וַתְּדַבֵּ֨ר מִרְיָ֤ם וְאַהֲרֹן֙ בְּמֹשֶׁ֔ה עַל־אֹד֛וֹת הָאִשָּׁ֥ה הַכֻּשִׁ֖ית אֲשֶׁ֣ר לָקָ֑ח כִּֽי־אִשָּׁ֥ה כֻשִׁ֖ית לָקָֽח׃ (ב) וַיֹּאמְר֗וּ הֲרַ֤ק אַךְ־בְּמֹשֶׁה֙ דִּבֶּ֣ר ה' הֲלֹ֖א גַּם־בָּ֣נוּ דִבֵּ֑ר וַיִּשְׁמַ֖ע יְהוָֽה׃ (ג) וְהָאִ֥ישׁ מֹשֶׁ֖ה ענו [עָנָ֣יו] מְאֹ֑ד מִכֹּל֙ הָֽאָדָ֔ם אֲשֶׁ֖ר עַל־פְּנֵ֥י הָאֲדָמָֽה׃ (ס) (ד) וַיֹּ֨אמֶר ה' פִּתְאֹ֗ם אֶל־מֹשֶׁ֤ה וְאֶֽל־אַהֲרֹן֙ וְאֶל־מִרְיָ֔ם צְא֥וּ שְׁלָשְׁתְּכֶ֖ם אֶל־אֹ֣הֶל מוֹעֵ֑ד וַיֵּצְא֖וּ שְׁלָשְׁתָּֽם׃ (ה) וַיֵּ֤רֶד ה' בְּעַמּ֣וּד עָנָ֔ן וַֽיַּעֲמֹ֖ד פֶּ֣תַח הָאֹ֑הֶל וַיִּקְרָא֙ אַהֲרֹ֣ן וּמִרְיָ֔ם וַיֵּצְא֖וּ שְׁנֵיהֶֽם׃ (ו) וַיֹּ֖אמֶר שִׁמְעוּ־נָ֣א דְבָרָ֑י אִם־יִֽהְיֶה֙ נְבִ֣יאֲכֶ֔ם ה' בַּמַּרְאָה֙ אֵלָ֣יו אֶתְוַדָּ֔ע בַּחֲל֖וֹם אֲדַבֶּר־בּֽוֹ׃ (ז) לֹא־כֵ֖ן עַבְדִּ֣י מֹשֶׁ֑ה בְּכָל־בֵּיתִ֖י נֶאֱמָ֥ן הֽוּא׃ (ח) פֶּ֣ה אֶל־פֶּ֞ה אֲדַבֶּר־בּ֗וֹ וּמַרְאֶה֙ וְלֹ֣א בְחִידֹ֔ת וּתְמֻנַ֥ת ה' יַבִּ֑יט וּמַדּ֙וּעַ֙ לֹ֣א יְרֵאתֶ֔ם לְדַבֵּ֖ר בְּעַבְדִּ֥י בְמֹשֶֽׁה׃
(1) Miriam and Aaron spoke against Moses because of the Cushite woman he had married: “He married a Cushite woman!” (2) They said, “Has the LORD spoken only through Moses? Has He not spoken through us as well?” The LORD heard it. (3) Now Moses was a very humble man, more so than any other man on earth. (4) Suddenly the LORD called to Moses, Aaron, and Miriam, “Come out, you three, to the Tent of Meeting.” So the three of them went out. (5) The LORD came down in a pillar of cloud, stopped at the entrance of the Tent, and called out, “Aaron and Miriam!” The two of them came forward; (6) and He said, “Hear these My words: When a prophet of the LORD arises among you, I make Myself known to him in a vision, I speak with him in a dream. (7) Not so with My servant Moses; he is trusted throughout My household. (8) With him I speak mouth to mouth, plainly and not in riddles, and he beholds the likeness of the LORD. How then did you not shrink from speaking against My servant Moses!”
Why wasn't Miriam's speech considered Lashon Hara Le'toelet?
Which principle of the "Chafetz Chayim" did Miriam seem to violate when speaking against her brother Moshe?
For Iyun: Biblical Stories of Lashon Hara:
1)See Shmot 4: 1-6, with Rashi's comment on Moshe's Lashon Hara
2)See Exodus 2:14 with Rashi's comment
3) See Genesis 37:2 with Rashi's comments.
Thinking Questions:
I speak negatively about my friend. He will never find out. Nor do the people involved plan on speaking Why is that such a terrible act?
What category would you put Lashon Hara in? Been Adam Lachaveyro? Been Adam Lamakom? Something else?

Why isn't Miriam's actions considered Lashon Hara Le'toelet-for a purpose?