Is it permissible to accompany the funeral of a disbeliever?

Abu Layla : What is our duty, as Muslims, when we enter the graves of the Christians to bury them?

The Shaykh : No;
Abu Layla: Not even her son?

The Shaykh : There is no objection to that, but accompanying the funeral and the like is not permissible. I am not saying bury her here or there, because I do not know how her life was conducted.
Abu Layla : Well, Shaykh, what about her children or those who see her daily?

The Shaykh : He did not give an answer to that.
Abu Layla : Yes, if for example we heard this tape now and said, "O her son and daughter, what will you testify about her?" Because you will be asked on the Day of Resurrection about this testimony, so clear yourselves before Allah. If her dealings, her prayer, and the like were like those of Muslims, then she is buried in the Muslims' graves. Otherwise, if her dealings, her manner, her speech, and her going to the church or the like were not so, then she is buried in the Christians' graves, and you are responsible for this.

The Shaykh : That is not what I am saying. My point revolves around this issue: we do not know about her life; they know better. So if they rule that she is a Muslim in practice, she is buried in the Muslims' graves; otherwise, in the Christians' graves. The ruling comes from them; we have only given them the principles.