Police Not Registering FIR And Considering A Murder As Suicide

Someone in the family fell from 4th floor of a building and died. His wife is claiming suicide, but there was no reason for him to do that. There's no note, and the wife herself found him lying in the back-street when she went all the way to the back-side of the terrace and saw him from above. The wife was evading police in giving her first statement at the hospital and has not been in contact with the in-laws at all, rather, has gone back to her family. Neither the wife nor family inquired about the last rites of the victim. There are multiple other small things that are weird even if looked at from a neutral point of view. The police have kind of decided that its a suicide case and are not ready to register an FIR at all. No interrogation/strict questioning of the wife has been done. We have filed a writ petition in High Court regarding this matter and prayed to the court that the case should be handed over to the crime branch or senior staff. Anything else left to do.