An ageing Father turns detective to convict son-in-law of daughter's murder

I’m interested for sure, it sounds topical and pulled from the headlines. I think it sounds like there would be great conflict and high stakes. I also think you would benefit by revealing what kind of man this father is — what was his past occupation? The logline itself could stand to be restructured and embellished a little so it makes more sense. Here’s an example of what I would probably say: “When his daughter is murdered, a former cop takes it upon himself to find the evidence that could convict his estranged son-in-law of the crime.”