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                                                                      EXHIBIT 11
 
              [LETTERHEAD OF SKADDEN, ARPS, SLATE, MEAGHER & FLOM]
 
                                                                 August 20, 1996
 
Van Kampen American Capital
  Tax Free Trust, on behalf of its series
  Van Kampen American Capital
  Municipal Income Fund
One Parkview Plaza
Oakbrook Terrace, IL 60181
 
     Re: Van Kampen American Capital Tax
         Free Trust -- Registration Statement
         on Form N-14 (File No. 333-6613)
 
Ladies and Gentlemen:
 
     We have acted as counsel to Van Kampen American Capital Tax Free Trust, a
Delaware business trust (the "Tax Free Trust"), on behalf of its series
designated as Van Kampen American Capital Municipal Income Fund (the "Municipal
Fund"), registered under the Investment Company Act of 1940, as amended (the
"1940 Act"), in connection with the preparation of the Tax Free Trust's
Registration Statement on Form N-14 (File No. 333-6613) as filed with the
Securities and Exchange Commission (the "Commission") on June 21, 1996, as
amended by Amendment No. 1 thereto to be filed with the Commission on or about
August 20, 1995 (the "Registration Statement").
 
     The Registration Statement relates to the registration under the Securities
Act of 1933, as amended (the "1933 Act"), of Class A, B and C shares of
beneficial interest, par value 0.01 per share, of the Municipal Fund (the
"Shares") to be issued in connection with the acquisition by the Municipal Fund
of the assets and assumption of the liabilities of the Van Kampen American
Capital Texas Tax Free Income Fund, a Delaware business trust (the "Texas
Fund"), pursuant to an Agreement and Plan of Reorganization by and between the
Tax Free Trust, on behalf of the Municipal Fund, and the Texas Fund.
 
     In connection with the foregoing, we have examined the originals or copies,
certified or otherwise identified to our satisfaction, of (i) the Registration
Statement; (ii) the Agreement and Declaration of Trust of the Tax Free Trust, as
amended to the date hereof; (iii) the Certificate of Trust of the Tax Free Trust
as filed with the Secretary of State of Delaware, as amended to the date hereof;
(iv) the By-laws of the Tax Free Trust, as amended to the date hereof; (v) the
Designation of Series of the Municipal Fund of the Tax Free Trust, as amended to
the date hereof; (vi) the form of Agreement and Plan of Reorganization (the
"Agreement"), which is included as an exhibit to the Registration Statement; and
(vii) copies of certain resolutions adopted by the Board of Trustees of the Tax
Free Trust and furnished to us by the Tax Free Trust relating to the
transactions contemplated by the Agreement. We have examined originals or
copies, certified or otherwise identified to our satisfaction, of such records
of the Tax Free Trust, and such agreements, certificates of public officials,
certificates of officers or representatives of the Tax Free Trust and others,
and such other documents, certificates and corporate or other records as we have
deemed necessary or appropriate as a basis for the opinions set forth herein.
 
     In our examination, we have assumed the capacity of natural persons, the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals, the conformity to original documents of all
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Van Kampen American Capital
  Tax Free Trust
August 20, 1996
Page 2

documents submitted to us as copies and the authenticity of the originals of
such latter documents. We have also assumed that the Agreement, when executed
and delivered by the parties thereto, will be in the form reviewed by us in
connection with this opinion. As to any facts material to our opinions expressed
herein which we did not independently establish or verify, we have relied on
oral or written statements and representations of officers and other
representatives of the Tax Free Trust and others.
 
     We are admitted to the bar in the State of Delaware and we express no
opinion as to the laws of any other jurisdiction.
 
     Based upon and subject to the foregoing, we are of the opinion that when
(i) the Registration Statement shall have become effective under the 1933 Act,
(ii) the Agreement is duly executed and delivered by the Tax Free Trust and the
other parties thereto, (iii) the Shares have been issued and delivered to the
Texas Fund in exchange for the assets and assumption of the liabilities of the
Texas Fund in accordance with the Agreement; and (iv) certificates representing
the Shares are duly executed, countersigned, registered and delivered, the
Shares will be validly issued, fully paid and nonassessable.
 
     Wayne W. Whalen, a Trustee of the Tax Free Trust and the Texas Fund, is a
partner in this Firm.
 
     We hereby consent to the filing of this opinion with the Commission as
Exhibit 11 to the Registration Statement. We hereby consent to the reference to
our Firm under the heading "THE PROPOSED REORGANIZATION -- Legal Matters" in the
Registration Statement. In giving this consent, we do not admit that we are in
the category of persons whose consent is required under Section 7 of the 1933
Act or the rules and regulations of the Commission.
 
                                       Very truly yours,

                                       /s/ Skadden, Arps, Slate, Meagher & Flom