Historically, epistolary novels (written as letters or diary entries) were popular in the 18th century. The criminal investigation files novel is the gritty, 21st-century evolution of that. Instead of letters, we have text messages, crime scene photos described in prose, and forensic lab reports.
You can adapt this "Case File" format for a book blurb or a project proposal: criminal investigation files novel
The roots of the investigation novel stretch back to the "ratiocination" stories of Edgar Allan Poe and the analytical prowess of Sherlock Holmes. Over time, the genre evolved through several distinct eras: Writing effective case summaries - Police1 Historically, epistolary novels (written as letters or diary