Answered by Ustadh Tabraze Azam
Question: In the past i have slandered some celebrities and politicians. Should I write letters to these people to apologize to them?
Answer: Wa alaikum assalam wa rahmatullah,
No, it is not necessary to seek the apology of the person you slandered if the slander did not or will not reach them. The scholars, thus, encourage that the person should instead simply seek forgiveness for their error. Moreover, it would be good to supplicate for the person spoken against or give something in charity on their behalf, for instance. However, when such a person is a non-Muslim, then any supplications should remain generic.
[Nabulsi, al-Hadiqa al-Nadiyya Sharh al-Tariqa al-Muhammadiyya (2.226)]
Please also see: What To Do When You Hear Slander and Backbiting and: What Can I Do to Repent From Slander When the Person I Have Spoke Ill of Does Not Want to Forgive Me? and: A Reader on Tawba (Repentance)
And Allah Most High alone knows best.
Checked & Approved by Shaykh Faraz Rabbani