If you are filing by mail you include all the tax forms for the MI return.
Note: I edited the answer due to the following:
I included the identify theft attachments and the instructions actually say to only include the tax forms.
https://www.michigan.gov/documents/taxes/MI_1040_Instruction_Book_Instructions_Only_609092_7.pdf
[Edited 4 -14-2019 9:28 AM PST]
