Longman Dictionary of Contemporary English
special interests
noun
EXAMPLES FROM CORPUS
▪ A must for anyone concerned with advertising to businesses, government, associations and consumer groups with special interests.
▪ Congress is not at its best when trying to reconcile the special interests that flock round energy bills.
▪ He said he wants to take power away from special interests and return it to voters.
▪ Other options are fraught with more complications because of the possibility of contributions from special interests.
▪ The influence of pressure groups and special interests will become pervasive.
▪ They could have the effect of simply making it cheaper for special interests to buy the system.
Wiktionary
special interests
n. A shadowy group with political power.