This is part of the Detective Series by Portal Games.
Description from the publisher:
Dig Deeper, written by Rob Daviau, is the first case in the Detective: Signature Series. The story transports players into an American town in the 1970s where their goal will be to solve the mystery of the death of a local politician.
The case is full of surprises and dripping with theme. Just like the base game, it is for 1-5 players and uses modern tools to enhance the investigation.