Digital Forensics may be used in cases of: unauthorized disclosure or copying of sensitive data, such as customer databases, price lists and employee payrolls, whether by accident or by intent; fraud and deception; Internet abuse by employees; industrial espionage, internal and external; recovery of data thought to be deleted or destroyed; revelation of data hidden or included in temporary or swap files; access to encrypted or password-protected data and many more. 

There's really no limit to what can be sought in a Digital Forensic investigation.