1
general::
Use the correct procedure, especially in a hierarchy or bureaucracy. For example, You'll have to go through channels for approval of this expenditure. This term uses channel in the sense of "a conduit." [Mid-1900s]
American Heritage Idioms
2
general::
Phrase(s): go through (the proper) channels
to use the proper procedure, working through the correct people and offices to get something done; to cooperate with a bureaucracy. • I’m sorry. I can’t help you. You’ll have to go through the proper channels. • I didn’t get what I wanted because I didn’t go through channels., Phrase(s): go through channels
Go to go through (the proper) channels.
McGrawhill's American Idioms And Phrasal Verbs