What is the ruling on placing the deceased in the grave lying on his back?

It is not permissible to place the deceased in the grave on their back. Rather, they must be directed towards the Qiblah. It is preferable to place them on their right side, and permissible on their left. If the deceased is buried facing a direction other than the Qiblah, it is obligatory to exhume the grave and reorient the deceased, unless the body has decomposed.