[COMERICA LETTERHEAD]

                                                                       EXHIBIT 5

                                          500 Woodward Avenue, 33rd Floor
                                          Detroit, Michigan  48226
                                          (313) 222-3432


March 31, 2003

Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C.  20549

RE:      COMERICA INCORPORATED -- REGISTRATION STATEMENT ON
         FORM S-8

Dear Sir/Madam:

I am Senior Vice President, Assistant Secretary and General Counsel-Investment
Bank and Corporate Finance to Comerica Incorporated, a Delaware corporation (the
"Corporation"). This opinion is being rendered with respect to the registration
statement on Form S-8 filed by the Corporation with the Securities and Exchange
Commission for the purpose of registering under the Securities Act of 1933 (the
"Act"), as amended, 90,000 shares of Common Stock, $5.00 par value, of the
Corporation (the "Securities"). The Securities are to be issued under the 1986
Stock Option Plan of Imperial Bancorp (the "Plan").

I have examined such certificates, instruments, and documents and reviewed such
questions of law as I have considered necessary or appropriate for the purposes
of this opinion, and, on the basis of such examination and review, I advise you
that, in my opinion:

The Securities have been duly authorized and, when issued in accordance with the
terms of the Plan, will be legally issued.

I hereby consent to the filing of this opinion as an exhibit to the registration
statement. In giving this consent, I do not thereby admit that I am within the
category of persons whose consent is required under Section 7 of the Act or the
rules and regulations of the Securities and Exchange Commission thereunder.

Very truly yours,

/s/ Mark W. Yonkman
Mark W. Yonkman, Esquire
Senior Vice President,
  Assistant Secretary and
  General Counsel-Investment
  Bank and Corporate Finance
Comerica Incorporated