Professors Wilkinson and Pickett’s “The Spirit Level”, originally published in 2009, is arguably one of the most important books on social inequality published in recent times, not just for the clear causal links it draws between inequality and a wide range of social issues such as crime, but also for it’s easy accessibility to students of all levels.
Fifteen years after it’s original publication the authors, in combination with the Equality Trust, have released a 2024 update to their original research that, in addition to adding important new data to the pot in areas like environmental issues, climate change and child poverty, has the distinct advantage in these straightened times of being available for free.
The Guardian also has an article containing an interesting overview of the new research from the authors that you might find useful.