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                                                                     EXHIBIT 5.2


                                  June 6, 1997










To Each of the Persons Listed
on Schedule I Attached Hereto

     RE:    TRENWICK CAPITAL TRUST I
            8.82% Exchange Subordinated Capital Income Securities

Ladies and Gentlemen:

            We have acted as special Delaware counsel for Trenwick Capital Trust
I, a Delaware business trust (the "Trust") in connection with the issuance of
its 8.82% Subordinated Income Capital Securities(TM) (SKIS(TM)) (the "Capital
Securities") and common securities (the "Common Securities") in connection with
the Amended and Restated Declaration of Trust (the "Declaration") entered into
as of January 31, 1997, by and among Trenwick Group Inc., as Sponsor, Chase
Manhattan Bank Delaware, as Delaware Trustee, The Chase Manhattan Bank, as
Property Trustee, and the Administrative Trustees named therein. Initially
capitalized terms used herein and not otherwise defined are used herein as
defined in the Declaration.

            For purposes of giving the opinions hereinafter set forth, we have
examined only the following documents and have conducted no independent factual
investigations of our own:

            1. The Certificate of Trust for the Trust, dated as of January 21,
1997 (the "Trust Certificate"), as filed in the Office of the Secretary of State
of the State of Delaware (the "Secretary of State") on January 21, 1997;
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            2. The original declaration of trust of the Trust, dated as of
January 21, 1997, by and between Trenwick Group Inc., as Sponsor and Chase
Manhattan Bank Delaware, as Delaware Trustee (the "Original Declaration");

            3. The Declaration;

            4. A Certificate of Good Standing for the Trust, dated June 6,
1997, obtained from the Secretary of State; and

            5. The form of Registration Statement on Form S-4 to be filed on the
date hereof (the "Registration Statement"), including a prospectus with respect
to the Trust (the "Prospectus"), relating to, among other things, an Exchange
Offer (the "Exchange Offer") involving the 8.82% Exchange Capital Securities of
the Trust representing preferred, undivided beneficial interests in the assets
of the Trust (each, an "Exchange Security" and collectively, the "Exchange
Securities" to be offered in exchange for the presently outstanding 8.82%
Subordinated Income Capital Securities(TM) (SKIS(TM)) of the Trust (the "Old
Securities"), filed by the Sponsor and the Trust with the Securities and
Exchange Commission.

            As to certain facts material to the opinions expressed herein, we
have relied upon the representations and warranties contained in the documents
examined by us all of which we have assumed to be true, complete and accurate in
all material respects. The documents referred to in paragraphs 1, 2, 3 and 5
above are collectively referred to as the "Agreements."

            Based upon the foregoing, and upon an examination of such questions
of law of the State of Delaware as we have considered necessary or appropriate,
and subject to the assumptions, qualifications, limitations and exceptions set
forth herein, we are of the opinion that:

            1. The Trust has been duly created and is validly existing in good
standing as a business trust under the Business Trust Act.

            2. The Exchange Securities will represent valid, and, subject to the
qualifications set forth in number 3 below, 
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fully paid and non-assessable undivided beneficial interests in the assets of
the Trust.

            3. The Holders of Exchange Securities, as beneficial owners of
Exchange Securities of the Trust, will be entitled to the same limitation of
personal liability extended to stockholders of private corporations for profit
organized under the General Corporation Law of the State of Delaware, except
that the Holders of Exchange Securities may be obligated to (a) provide
indemnity and/or security in connection with and pay taxes or governmental
charges arising from transfers or exchanges of certificates representing
Exchange Securities and the issuance of replacement certificates representing
Exchange Securities, (b) provide security or indemnity in connection with
requests of or directions to the Property Trustee to exercise its rights and
powers under the Declaration, and (c) provide indemnity in connection with
violations of the Declaration or federal or state securities laws arising from
transfers or exchanges of certificates representing Exchange Securities and the
issuance of replacement certificates representing Exchange Securities.

            All of the foregoing opinions contained herein are subject to the
following assumptions, qualifications, limitations and exceptions:

                  a. The foregoing opinions are limited to the laws of the State
of Delaware presently in effect, excluding the securities laws thereof. We have
not considered and express no opinion on the laws of any other jurisdiction,
including, without limitation, federal laws and rules and regulations relating
thereto.

                  b. We have assumed the due execution and delivery by each
party listed as a party to each document examined by us. We have assumed further
the due authorization by each party thereto (exclusive of the Trust) of each
document examined by us, and that each of such parties (exclusive of the Trust)
has the full corporate, or trust or banking, power, authority, and legal right
to execute, deliver and perform each such document. We also have assumed that
each of the parties to each of the Agreements (exclusive of the Trust and the
Administrative Trustees) is a corporation, bank, national banking association or
trust company, validly existing and in good standing under the laws of their
respective jurisdictions 
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of organization and that the Agreements to which they are a party do not result
in the breach of the terms of, and do not contravene their respective
constituent documents, any contractual restriction binding on them or any law,
rule or regulation applicable to them. In addition, we have assumed the legal
capacity of any natural persons who are parties to any of the documents examined
by us.

                  c. We have assumed that all signatures on documents examined
by us are genuine, that all documents submitted to us as originals are authentic
and that all documents submitted to us as copies conform with the originals.

                  d. We have assumed that the Original Declaration and the
Declaration collectively, constitute the entire agreement among each of the
respective parties thereto with respect to the subject matter thereof, including
with respect to the creation, operation, dissolution and winding up of the Trust
and that the Declaration and the Certificate are in full force and effect.

                  e. We have assumed that no event set forth in Article 9 of the
Declaration has occurred.

                  f. We have assumed that the Exchange Securities will be issued
and exchanged in accordance with the Declaration and the Prospectus. We have
further assumed the receipt of each Person to whom a Exchange Security is to be
issued by the Trust of a Certificate for such Exchange Security and the exchange
by it of an equivalent liquidation amount of Old Securities in accordance with
the Declaration and the Prospectus.

                  g. We note that we have not participated in the preparation,
and do not assume responsibility for the contents, of the Registration Statement
or the Prospectus.

            We consent to the filing of this opinion with the Securities and
Exchange Commission as an exhibit to the Registration Statement. In addition, we
hereby consent to the use of our name under the heading "Validity of Exchange
Securities" in the Prospectus. In giving the foregoing consents, we do not
thereby admit that we come within the category of Persons whose consent is
required under Section 7 of the Securities Act of 1933, as amended, or the rules
and
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regulations of the Securities and Exchange Commission thereunder.

                                    Very truly yours,
                                       
                                    /s/ Potter Anderson & Corroon
                                    -------------------------------- 

259849
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                                   SCHEDULE I


TRENWICK GROUP INC.