Don't know if these answer your query:
WT 15th July 1959
? Is it proper for a brother to conduct the funeral service of an individual who was never associated with Jehovah's witnesses and who committed suicide?-K. L., U.S.A.
This all depends on the conscientious attitude of the brother in the truth who may be requested to perform the funeral service. If his conscience revolts against the thought because of self-murder, then he should not violate his conscience by performing the ceremony. If another capable brother feels that he can conscientiously do so, there is no objection to his doing so. Whereas he cannot preach the suicide into heaven or even hold forth Scriptural promises that the suicide will have an opportunity for life in the new world, and although he does not condone the suicide, yet he appreciates that the holding of a funeral service affords a marvelous opportunity to give a witness to God's kingdom and the blessings that it will bring to mankind, including the resurrection of the dead.