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                                                                     Exhibit 8.1

                                  June 12, 2003


Brandywine Realty Trust
401 Plymouth Road
Suite 500
Plymouth Meeting, PA  19462


Ladies and Gentlemen:

                  We have acted as counsel to Brandywine Realty Trust, a
Maryland real estate investment trust (the "Company"), in connection with the
preparation of a Registration Statement on Form S-3 (333-56237)(the
"Registration Statement"). You have requested our opinion on certain federal
income tax matters in connection with the Registration Statement.

Basis for Opinions

                  The opinions set forth in this letter are based on the
Internal Revenue Code of 1986, as amended (the "Code"), Treasury regulations
thereunder (including proposed and temporary Treasury regulations), and
interpretations of the foregoing as expressed in court decisions, legislative
history and administrative determinations of the Internal Revenue Service (the
"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. An opinion of counsel merely
represents counsel's best judgment with respect to the probable outcome on the
merits and is not binding on the IRS or the courts. There can be no assurance
that positions contrary to our opinions will not be taken by the IRS, or that a
court considering the issues would not reach a conclusion contrary to such
opinions. Furthermore, no assurance can be given that future legislative,
judicial or administrative changes, on either a prospective or retroactive
basis, would not adversely affect the accuracy of the opinions expressed herein.
Nevertheless, we undertake no responsibility to advise you of any new
developments in the law or in the application or interpretation of the federal
income tax laws.

                  In rendering the following opinions, we have examined such
statutes, regulations, records, certificates and other documents as we have
considered necessary or appropriate as a basis for such opinions, including (but
not limited to) the following: (1) the Registration Statement and Prospectus
(including the various SEC filings incorporated therein by reference); (2) the
Amended and Restated Declaration of Trust of Company, as amended or supplemented
through the date hereof including, with respect to each series of preferred
shares of beneficial interest of the Company, the articles supplementary
establishing and fixing the rights and preferences of such series of preferred
shares of beneficial interest; (3) the Amended and Restated Agreement of Limited

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Partnership, as amended or supplemented through the date hereof, of Brandywine
Operating Partnership, L.P., a Delaware limited partnership (the "Operating
Partnership"); and (4) the Declaration of Trust, as amended or supplemented
through the date hereof, of Atlantic American Properties Trust, a Maryland real
estate investment trust ("AAPT").

                  In providing the opinions set forth in this letter, we have
relied upon written representations as to factual matters of (i) the Company and
the Operating Partnership contained in a letter to us dated June 12, 2003,
regarding their assets, operations and activities and (ii) AAPT contained in a
letter to us dated June 12, 2003, regarding its assets, operations and
activities (collectively, the "Management Representation Letters").

                  For purposes of rendering our opinion, we have not made an
independent investigation or audit of the facts set forth in any of the
above-referenced documents, including the Management Representation Letters. We
consequently have relied upon the representations as to factual matters in the
Management Representation Letters. After inquiry, we are not aware of any facts
or circumstances contrary to, or inconsistent with, the representations that we
have relied upon as referenced herein or other assumptions set forth herein.
Finally, our opinion is limited to the tax matters specifically covered herein,
and we have not addressed, nor have we been asked to address, any other tax
matters relevant to the Company, the Operating Partnership, AAPT or any other
person.

                  Moreover, we have assumed, with your consent, that, insofar as
relevant to the opinions set forth herein:

                  (1) the Company, the Operating Partnership and AAPT have been
and will be operated in the manner described in the Management Representation
Letters and the Registration Statement (including the filings by the Company
with the Commission incorporated therein by reference);

                  (2) all of the obligations imposed by the documents that we
reviewed have been and will continue to be performed or satisfied in accordance
with their terms;

                  (3) all representations made in the Management Representation
Letters (and other information provided to us) are true, correct and complete
and will continue to be true, correct and complete, and any representation or
statement made in the Management Representation Letters "to the best of
knowledge," "to the knowledge," or "to the actual knowledge" of any person(s) or
party(ies) or similarly qualified is true, correct and complete as if made
without such qualification; and

                  (4) all documents that we have reviewed have been properly
executed, are valid originals or authentic copies of valid originals, and all
signatures thereon are genuine.
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Opinions

                  Based upon, subject to, and limited by the assumptions and
qualifications set forth herein, we are of the opinion that:

                  (1) commencing with its taxable year ended December 31, 1986,
the Company has been organized and has operated in conformity with the
requirements for qualification and taxation as a real estate investment trust
("REIT") under the Code; and based on the facts and assumptions set forth herein
and in the Management Representation Letters regarding certain federal income
tax matters, the Company's method of operation has enabled it, and its proposed
method of operation will enable it, to meet the requirements under the Internal
Revenue Code of 1986, as amended, for qualification and taxation as a REIT.

                  (2) the portions of the discussion in the Current Report on
Form 8-K filed with the Commission on June 12, 2003, and incorporated by
reference into the Registration Statement, under the caption "Material Federal
Income Tax Consequences", as set forth in Exhibit 99.1 thereto, to the extent
they describe applicable U.S. federal income tax law, are correct in all
material respects as of the date hereof (but no opinion is expressed herein as
to proposed changes to U.S. federal income tax law), and the discussions
contained therein are accurate and fair summaries of the federal income tax
considerations that may be material to a holder of Common Shares.

                  We assume no obligation to advise you of any changes in our
opinions subsequent to the date of this letter. The Company's qualification and
taxation as a REIT depend upon (i) the Company's ability to meet on a continuing
basis, through actual annual operating and other results, the requirements of
the Code, including the requirements with regard to the sources of its gross
income, the composition of its assets, the level of its distributions to
shareholders, and the diversity of its share ownership; and (ii) the
satisfaction by AAPT on a continuing basis of the requirements for qualification
and taxation as a REIT. We will not review the Company's or AAPT's compliance
with these requirements on a continuing basis. Accordingly, no assurance can be
given that the actual results of Company's operations, the sources of its
income, the nature of its assets, the level of its distributions to
shareholders, and the diversity of its share ownership for any given taxable
year will satisfy the requirements under the Code for qualification and taxation
as a REIT.

                  This opinion letter has been prepared for your use in
connection with the filing of the Registration Statement and speaks of the date
hereof. We hereby consent to the incorporation by reference of this opinion
letter as Exhibit 8.1 to the Registration Statement, and to references to Pepper
Hamilton LLP in the Registration Statement. In giving this consent, however, we
do not admit thereby that we are an "expert" within the meaning of the
Securities Act of 1933, as amended.

                                                          Very truly yours,



                                                         PEPPER HAMILTON LLP





