It was narrated to us by Aḥmed bin Hārūn رضي الله عنه, who said – it was narrated to us by Moḥammed bin ʿAbd Allāh, from his father ʿAbd Allāh bin Jaʿfar bin Jāmiʿ, from Aḥmed bin Moḥammed al-Barqi, from Hārūn bin al-Juham:1

From al-Ṣādiq Jaʿfar bin Moḥammed عليهما السلام, who said: If the dissolute announces his debauchery, then there is no sacrosanctity for him, nor is there any [prohibition on] backbiting.

1. Shaykh Hādi al-Najafi says the chain is reliable. [Mawsūʿat al-Aḥādīth ahl al-Bayt, Volume 8, Page 465]; Sayed al-Khomeini has said it has a good chain [al-Mukāsib al-Muḥarama, Volume 1, Page 276], and Muḥaqiq al-Baḥrāni has graded it authentic [al-Ḥadā’iq al-Nādhirah, Volume 18, Page 166]. Others, like Sayid al-Khū’i have graded the chain as weak – despite claiming the content being sound.
The main differences in gradings come from Aḥmed bin Hārūn, the shaykh of al-Ṣadūq, being in the chain. Despite al-Ṣadūq doing tarādhi upon him, some do not believe his reliability is established.

حدثنا أحمد بن هارون ( رضي الله عنه ) ، قال : حدثنا محمد بن عبد الله ، عن أبيه عبد الله بن جعفر بن جامع ، عن أحمد بن محمد البرقي ، عن هارون بن الجهم ، عن الصادق جعفر بن محمد ( عليهما السلام ) ، قال : إذا جاهر الفاسق بفسقه فلا حرمة له ولا غيبة