Principle 2 9from Chafetz Chaim

וְכָל זֶה שֶׁדִּבַּרְנוּ הוּא מִצַּד אִסוּר הָאֲמִירָה בְּעַצְמוֹ, אֲבָל, חַס וְשָׁלוֹם, לְהוֹסִיף אְפִלּוּ תֵּבָה אַחַת אוֹ לְהַטְעִים אֶת הַדָּבָר בִּפְנֵי הַשּׁוֹמֵעַ, לוֹמַר שֶׁהַמַּעֲשֶׂה שֶׁנִּשְׁמַע עַל שִׁמְעוֹן, יָפֶה נִשְׁמָע עָלָיו וְכַיּוֹצֵּא בָּזֶה, זֶה וַדַּאי אָסוּר בְּכָל גַּוְנֵי, דְּהוּא מְּקַלְקֵל אוֹתוֹ בִּדְבָרָיו, יוֹתֵר מִמַּה שֶּׁהָיָה נִשְׁמָע עָלָיו לְבַסוֹף מֵעַצְּמוֹ עַל פִּי הַסְּבָרָא דְּאַפֵּי תְּלָתָא. וְעוֹד, דְּבָזֶה מוּכָח שֶׁמְּקַבֵּל דָּבָר זֶה לֶאֱמֶת, וְזֶה אָסוּר לְכֻלֵּי עָלְמָא בְּבָל גּוְנֵי, וּכְמוֹ שֶׁיִּתְבָּאֵר אִם יִרְצֶּה ה' לְקַמָּן בִּכְלָל ז' סָעִיף א', עַיֵּן שָׁם.

And all this that we have said applies to the issur of repeating it itself, but (G–d forbid) to add even one word or to "embroider" the thing before the hearer, as by saying that what was said against Shimon was very well said, and the like — this certainly is forbidden in all modes, for he thereby harms him with his words more than he would have been harmed had he himself heard [the original report] within the normal dynamics of apei telata. And, furthermore, by this [adding to the original], it is clear that he accepts the report as true, and this is forbidden by all [poskim] in all modes, as will be explained below, please G–d, in Principle VII, section 1.

וְעַל כֵּן צָּרִיךְ לִזָּהֵר מְאֹד, אֲפִלּוּ אִם מְפֻרְסָם (כ) עַל אָדָם עִנְיָן אֶחָד לְרַע שֶׁעָשָׂה בְּנַעְרוּתוֹ, אַךְ מֵאָז וְעַד עַתָּה הוּא מִתְנַהֵג כַּשּׁוּרָה, אוֹ שֶׁמְּפֻרְסָם עַל אֲבוֹתָיו, שֶׁלֹּא הָיוּ נוֹהֲגִים כַּשּׁוּרָה כְּלָל, וְהוּא אֵינוֹ אוֹחֵז בְּדַרְכֵיהֶם, וְכָל כְּהַאי גַּוְנָא {וכל כיוצא בזה} בְּדָבָר שֶׁעַל פִּי אֱמֶת אֵין עַוְלָה עָלָיו, אָסוּר לְגַנּוֹתוֹ וּלְבַזּוֹתוֹ אֵצֶּל חֲבֵרָיו בָּזֶה, וּמִי שֶׁהוּא עוֹבֵר עַל זֶה וּמְסַפֵּר בִּדְבָרִים אֵלּוּ בִּפְנִי בְּנֵי אָדָם, אֲפִלּוּ שֶׁלֹּא בְּפָנָיו, כְּדֵי לְבַזּוֹתוֹ בְּעֵינִי עַמּוֹ, אֲפִלּוּ לֹא יוֹסִיף שׁוּם דָּבָר עַל הָאֱמֶת, הוּא מִכְּלַל כַּת מְסַפְּרֵי לָשׁוֹן הָרָע, שֶׁאֵינָם מְקַבְּלִים פְּנִי שְׁכִינָה, כְּמוֹ שֶׁכָּתַב בְּשַׁעֲרֵי תְּשׁוּבָה בְּמַאֲמָר רי"ד, וְלֹא שַׁיָּךְ עַל זֶה כְּלָל הֶתֵּרָא דְּאַפֵּי תְּלָתָא {ההתר של בפני שלושה}, אַף שֶׁדָּבָר זֶה מְפֻרְסָם בְּפִי כֹּל, אַחֲרֵי שֶׁעַל פִּי אֱמֶּת אֵין עָלָיו שׁוּם גְּנַאי בָּזֶה, כְּמוֹ שֶׁכָּתַב בִּיחֶזְקֵאל י"ח: "בֶּן לֹא יִשָּׂא בַּעֲוֹן הָאָב וְגוֹ' כָּל פְּשָׁעָיו אֲשֶׁר עָשָׂה לֹא יִזָּכְרוּ" וְגוֹ' וְהוּא עוֹשֵׂהוּ עֲבוּר זֶה לְלַעַג בְּפִי הַבְּרִיּוֹת.

And, therefore, one must take great heed, even if a man is known to have had a certain fault in his youth, but from then until now he has been conducting himself correctly; or if it is known about his forbears that they did not conduct themselves correctly at all, but he does not hold on to their ways, and all such things, where, in truth, he is not open to aspersion, it is forbidden to demean him or to shame him before his friends because of this [early fault]. And one who transgresses and speaks about these things before others, even if not in his presence, in order to shame him in the eyes of his people, even if he adds nothing to the truth, is in the class of the speakers of lashon hara, who do not behold the Divine Presence, as stated in Sha'arei Teshuvah 214. And the heter of apei telata does not apply in such an instance, even if the thing is known to all, since, in truth, he [the object of this report] bears no blemish in this, as written in Yechezkel (18:20-22): "The son shall not bear the sin of the father. And the wicked one, when he turns from all his sins which he has done… All of the sins which he has done shall not be reckoned unto him in his righteousness. In the righteousness which he has done shall he live." And he [who does bring these things up to him] renders him a mockery in the mouths of men.