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September 13, 2000
Morgan Stanley Dean Witter Tax-Exempt Securities Trust
Two World Trade Center
New York, New York 10048
Ladies and Gentlemen:
This opinion is being furnished to Morgan Stanley Dean Witter Tax-Exempt
Securities Trust, a Massachusetts business trust ("Tax-Exempt"), in connection
with the Registration Statement on Form N-14 (the "Registration Statement")
under the Securities Act of 1933, as amended (the "1933 Act"), to be filed by
Tax-Exempt in connection with the acquisition by Tax-Exempt, of substantially
all the assets of Morgan Stanley Dean Witter Municipal Income Trust II, a
Massachusetts business trust ("MIT II"), in exchange for shares of beneficial
interest of Tax-Exempt ("Shares") and the assumption by Tax-Exempt of certain
stated liabilities of MIT II pursuant to an Agreement and Plan of
Reorganization dated as of August 24, 2000 (the "Reorganization Agreement"). We
have examined such statutes, regulations, corporate records and other documents
and reviewed such questions of law as we deemed necessary or appropriate for
the purposes of this opinion.
As to matters of Massachusetts law contained in this opinion, we have
relied upon the opinion of Nutter, McClennen & Fish LLP, dated September 12,
2000.
Based upon the foregoing, we are of the opinion that the Shares when
issued, as described in the Reorganization Agreement, will be duly authorized
and, assuming receipt of the consideration to be paid therefor, upon delivery
as provided in the Reorganization Agreement, will be legally issued, fully paid
and non-assessable (except for the potential liability of shareholders
described in Tax-Exempt's Statement of Additional Information dated February
24, 2000 under the caption "Capital Stock And Other Securities").
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to us under the caption "Legal
Matters" in the Prospectus forming a part of the Registration Statement. We do
not thereby admit that we are within the category of persons whose consent is
required under Section 7 of the 1933 Act or the rules and regulations of the
Securities and Exchange Commission thereunder.
Very truly yours,
/s/ Mayer, Brown & Platt
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Mayer, Brown & Platt
