Heaven's Prisoners is the second Dave Robicheaux title by James Lee Burke. It has dropped to £2.99 at Kindle UK, which is not a great price IMO for a book that is more than three decades old, but is still much better than its normal £5.49. So, here are links/info...
Kindle UK:
https://www.amazon.co.uk/dp/B003TO59TQ
Kindle UK/Smile:
https://smile.amazon.co.uk/dp/B003TO59TQ
Note that there was an omnibus of many of the early Robicheaux titles that was on sale several years ago. So check carefully before you buy...