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                                                                     EXHIBIT 8.1

           [LIDDELL, SAPP, ZIVLEY, HILL & LABOON, L.L.P. LETTERHEAD]


                                 March 24, 1998



American Industrial Properties REIT
6224 N. Beltline Road, Suite 205
Irving, Texas  75063
Attention:  Charles W. Wolcott, President

Re:      Certain Federal Income Tax Matters

Ladies and Gentlemen:

         This opinion is delivered to you in our capacity as counsel to
American Industrial Properties REIT (the "Company") in connection with the
Company's registration statement on Form S-3 (the "Registration Statement")
filed by the Company with the Securities and Exchange Commission under the
Securities Act of 1933, as amended, relating to the registration of 1,000,000
shares of the Company's common stock, par value $0.10 per share, that may be
issued by the Company pursuant to the Company's Dividend Reinvestment and Stock
Purchase Plan.  This opinion relates to the Company's qualification for federal
income tax purposes as a real estate investment trust ("REIT") under the
Internal Revenue Code of 1986, as amended (the "Code"), and the accuracy of the
discussion under the heading "Tax Consequences of Participation in the Plan"
contained in the registration Statement.

         The opinions set forth in this letter are based on relevant provisions
of the Code, Treasury Regulations promulgated thereunder (including proposed
and temporary Regulations), and interpretations of the foregoing as expressed
in court decisions, the legislative history and existing administrative rulings
and practices of the Internal Revenue Service ("IRS") (including its practices
and policies in issuing private letter rulings, which are not binding on the
IRS except with respect to a taxpayer that receives such a ruling), all as of
the date hereof.  These provisions and interpretations are subject to change,
which may or may not be retroactive in effect, that might result in
modifications of our opinion.

         In rendering the following opinion, we have examined such statutes,
regulations, records, certificates and other documents as we have considered
necessary or appropriate as a basis for such
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opinion, including the following: (1) the Third Amended and Restated
Declaration of Trust and Fourth Amended and Restated Bylaws of the Company as
amended to date; (2) certain written representations of the Company contained
in an Officer's Certificate to Counsel for American Industrial Properties REIT
Regarding Certain Income Tax Matters, dated March 24, 1998; and (3) such other
certificates, documents, agreements and instruments as we have considered
necessary or appropriate.

         We have reviewed the Registration Statement and the description set
forth therein of the Company and its investments and activities. We have relied
upon the representations of the Company and its affiliates and certain officers
thereof regarding the manner in which the Company has been and will continue to
be owned and operated. We have neither independently investigated nor verified
such representations, and we assume that such representations are true, correct
and complete and that all representations made "to the best of the knowledge
and belief" of any person(s) or party(ies) or with similar qualification are
and will be true, correct and complete as if made without such qualification.
We assume that the Company has been and will be operated in accordance with
applicable laws and the terms and conditions of applicable documents, and that
the descriptions of the Company and its investments, and the proposed
investments, activities, operations and governance of the Company set forth in
the Registration Statement continue to be true. In addition, we have relied on
certain additional facts and assumptions described below.

         In rendering the opinion set forth herein, we have assumed (i) the
genuineness of all signatures on documents we have examined, (ii) the
authenticity of all documents submitted to us as originals, (iii) the
conformity to the original documents of all documents submitted to us as
copies, (iv) the conformity of final documents to all documents submitted to us
as drafts, (v) the authority and capacity of the individual or individuals who
executed any such documents on behalf of any person, (vi) the accuracy and
completeness of all records made available to us, and (vii) the factual
accuracy of all representations, warranties and other statements made by all
parties. We also have assumed, without investigation, that all documents,
certificates, warranties and covenants on which we have relied in rendering the
opinion set forth below and that were given or dated earlier than the date of
this letter continue to remain accurate, insofar as relevant to the opinion set
forth herein, from such earlier date through and including the date of this
letter.

         Based upon and subject to the foregoing, and provided that the Company
continues to meet the applicable asset composition, source of income,
shareholder diversification, distribution, record keeping and other
requirements of the Code necessary for a corporation to qualify as a REIT, we
are of the opinion that:

         1.      Commencing with the Company's first taxable year ended
                 December 31, 1985, the Company has been organized in
                 conformity with the requirements for qualification as
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                 a REIT under the Code, and the Company's method of operation,
                 as described in the representations referred to above, will
                 enable it to continue to meet the requirements for
                 qualification and taxation as a REIT under the Code.

         2.      The statements in the Registration Statement set forth under
                 the heading "Tax Consequences of Participation in the Plan" to
                 the extent such information constitutes matters of law,
                 summaries of legal matters, or legal conclusions, have been
                 reviewed by us and are accurate to all material respects.

         We assume no obligation to advise you of any changes in our opinion
subsequent to the delivery of this opinion letter.  The Company's qualification
as a REIT depends upon the Company's ability to meet on a continuing basis,
through actual annual operating and other results, the various requirements
under the Code with regard to, among other things, the sources of its gross
income, the composition of its assets, the level of its distributions to
stockholders, and the diversity of its stock ownership.  We have not undertaken
to review or audit the Company's compliance with these requirements on a
continuing basis.  Accordingly, no assurance can be given that the actual
operating results of the Company, and the entities in which the Company owns
interests, the sources of their income, the nature of their assets, the level
of distributions to shareholders and the diversity of stock ownership for any
given taxable year has satisfied or will satisfy the requirements under the
Code for qualification and taxation as a REIT.

         We express no opinion herein other than those expressly set forth
herein. You should recognize that our opinion is not binding on the IRS and
that the IRS may disagree with the opinion contained herein. Although we
believe that our opinion will be sustained if challenged, there can be no
assurance that this will be the case. The opinion expressed herein is based
upon the law as it currently exists. Consequently, future changes in the law
may cause the federal income tax treatment of the transactions described herein
to be materially and adversely different from that described above.

         This opinion letter may not be used or relied upon by any other person
or for any other purpose and may not be disclosed, quoted, filed with a
governmental agency or otherwise referred to without our prior written consent.
Notwithstanding the foregoing, we hereby consent to being named as counsel to
the Company in the REGISTRATION STATEMENT, to the references in the
Registration Statement to our firm and to the inclusion of a copy of this
opinion letter as an exhibit
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to the REGISTRATION STATEMENT.  In giving such consent, we do not thereby admit
that we are an "expert" within the meaning of the Securities Act of 1933, as
amended.

                               Sincerely yours,

                               /s/ Liddell, Sapp, Zivley, Hill & LaBoon, L.L.P.

                               Liddell, Sapp, Zivley, Hill & LaBoon, L.L.P.