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                                                                     Exhibit 4.8

                                 TRUST AGREEMENT


         THIS TRUST AGREEMENT, dated as of October 2, 2003, between RLI Corp.,
an Illinois corporation, as depositor and sponsor (the "Depositor" or
"Sponsor"), and Wilmington Trust Company, a Delaware banking corporation, which
is acting hereunder not in its individual capacity but solely as property
trustee and Delaware trustee (the "Trustee"). The Depositor and the Trustee
hereby agree as follows:

         1.  CREATION OF TRUST.

         (a) The trust created hereby shall be known as "RLI Capital Trust I".

         (b) The Depositor hereby assigns, transfers, conveys and sets over to
the Trustee the sum of $1.00. The Trustee hereby acknowledges receipt of such
amount in trust from the Depositor, which amount shall constitute the initial
trust estate. The Trustee hereby declares that it will hold the trust estate in
trust for the Depositor. It is the intention of the parties hereto that the
Trust created hereby constitute a statutory trust under Chapter 38 of Title 12
of the Delaware Code, 12 DEL. C. Section 3801 ET SEQ. and that this Trust
Agreement constitute the governing instrument of the Trust. The Trustee is
hereby authorized and directed to execute and file a certificate of trust with
the Delaware Secretary of State in the form attached hereto.

         (c) The Trustee is authorized to enter into an amended and restated
trust agreement and further authorized and directed to enter into such other
documents and take such other action as the Depositor specifically directs in
written instructions delivered to the Trustee; provided, however, the Trustee
shall not be required to take any action if the Trustee shall determine, or
shall be advised by counsel, that such action is likely to result in personal
liability or is contrary to applicable law or any agreement to which the Trustee
is a party.

         2.  CONCERNING THE TRUSTEE.

         (a) Except as otherwise expressly required by Section 1 of this Trust
Agreement, the Trustee shall not have any duty or liability with respect to the
administration of the Trust, the investment of the Trust's property or the
payment of dividends or other distributions of income or principal to the
Trust's beneficiaries, and no implied obligations shall be inferred from this
Trust Agreement on the part of the Trustee. The Trustee shall not be liable for
the acts or omissions of the Depositor nor shall the Trustee be liable for any
act or omission by it in good faith in accordance with the directions of the
Depositor.

         (b) The Trustee accepts the trusts hereby created and agrees to perform
its duties hereunder with respect to the same but only upon the terms of this
Trust Agreement. The Trustee shall not be personally liable under any
circumstances, except for its own willful misconduct or negligence. In
particular, but not by way of limitation:

                   (i)   The Trustee shall not be personally liable for any
error of judgment made in good faith by an officer or employee of the Trustee;

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                   (ii)  No provision of this Trust Agreement shall require the
Trustee to expend or risk its personal funds or otherwise incur any financial
liability in the performance of its rights or duties hereunder, if the Trustee
shall have reasonable grounds for believing that repayment of such funds or
adequate indemnity against such risk or liability is not reasonably assured or
provided to it;

                   (iii) Under no circumstance shall the Trustee be personally
liable for any representation, warranty, covenant or indebtedness of the Trust;

                   (iv)  The Trustee shall not be personally responsible for or
in respect of the genuineness, form or value of the Trust property, the validity
or sufficiency of this Trust Agreement or for the due execution hereof by the
Depositor;

                   (v)   In the event that the Trustee is unsure of the course
of action to be taken by it hereunder, the Trustee may request instructions from
the Depositor and to the extent the Trustee follows such instructions in good
faith it shall not be liable to any person. In the event that no instructions
are provided within the time requested by the Trustee, it shall have no duty or
liability for its failure to take any action or for any action it takes in good
faith;

                   (vi)  All funds deposited with the Trustee hereunder may be
held in a non-interest bearing trust account and the Trustee shall not be liable
for any interest thereon or for any loss as a result of the investment thereof
at the direction of the Depositor; and

                   (vii) To the extent that, at law or in equity, the Trustee
has duties and liabilities relating thereto to the Depositor or the Trust, the
Depositor agrees that such duties and liabilities are replaced by the terms of
this Trust Agreement.

         (c) The Trustee shall incur no liability to anyone in acting upon any
document believed by it to be genuine and believed by it to be signed by the
proper party or parties. The Trustee may accept a certified copy of a resolution
of the board of directors or other governing body of any corporate party as
conclusive evidence that such resolution has been duly adopted by such body and
that the same is in full force and effect. As to any fact or matter the manner
of ascertainment of which is not specifically prescribed herein, the Trustee may
for all purposes hereof rely on a certificate, signed by the Depositor, as to
such fact or matter, and such certificate shall constitute full protection to
the Trustee for any action taken or omitted to be taken by it in good faith in
reliance thereon.

         (d) In the exercise or administration of the trusts hereunder, the
Trustee (i) may act directly or, at the expense of the Trust, through agents or
attorneys, and the Trustee shall not be liable for the default or misconduct of
such agents or attorneys if such agents or attorneys shall have been selected by
the Trustee in good faith, and (ii) may, at the expense of the Trust, consult
with counsel, accountants and other experts, and it shall not be liable for
anything done, suffered or omitted in good faith by it in accordance with the
advice or opinion of any such counsel, accountants or other experts.

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         (e) Except as expressly provided in this Section 2, in accepting and
performing the trusts hereby created, the Trustee acts solely as trustee
hereunder and not in its individual capacity, and all persons having any claim
against the Trustee by reason of the transactions contemplated by this Trust
Agreement shall look only to the Trust's property for payment or satisfaction
thereof.

         3.  COMPENSATION AND INDEMNIFICATION.

         (a) The Depositor hereby agrees to (i) compensate the Trustee in
accordance with a separate fee agreement with the Trustee, (ii) reimburse the
Trustee for all reasonable expenses (including reasonable fees and expenses of
counsel and other experts) and (iii) indemnify, defend and hold harmless the
Trustee (including in its individual capacity) and any of the officers,
directors, employees and agents of the Trustee (the "Indemnified Persons") from
and against any and all losses, damages, liabilities, claims, actions, suits,
costs, expenses, disbursements (including the reasonable fees and expenses of
counsel), taxes and penalties of any kind and nature whatsoever (collectively,
"Expenses"), to the extent that such Expenses arise out of or are imposed upon
or asserted at any time against such Indemnified Persons with respect to the
performance of this Trust Agreement, the creation, operation or termination of
the Trust or the transactions contemplated hereby; PROVIDED, HOWEVER, that the
Depositor shall not be required to indemnify any Indemnified Person for any
Expenses which are a result of the willful misconduct, bad faith or negligence
of such Indemnified Person.

         (b) To the fullest extent permitted by law, Expenses to be incurred by
an Indemnified Person shall, from time to time, be advanced by, or on behalf of,
the Depositor prior to the final disposition of any matter upon receipt by the
Depositor of an undertaking by, or on behalf of, such Indemnified Person to
repay such amount if it shall be determined that the Indemnified Person is not
entitled to be indemnified under this Agreement.

         4. The Trustee may resign upon thirty days prior notice to the
Depositor. If no successor has been appointed within such thirty day period, the
Trustee may, at the expense of the Trust, petition a court to appoint a
successor trustee. Any Person into which the Trustee may be merged or with which
it may be consolidated, or any Person resulting from any merger or consolidation
to which the Trustee shall be a party, or any Person which succeeds to all or
substantially all of the corporate trust business of the Trustee, shall be the
successor Trustee under this Trust Agreement without the execution, delivery or
filing of any paper or instrument or further act to be done on the part of the
parties hereto, except as may be required by applicable law.

         5. The Depositor is hereby authorized, in its discretion,

         (a) to prepare and file with the Securities and Exchange Commission
(the "Commission") and to execute, in the case of the 1933 Act Registration
Statement and 1934 Act Registration Statement (each as herein defined), on
behalf of the Trust, (i) a Registration Statement (the "1933 Act Registration
Statement"), including all pre-effective and post-effective amendments thereto,
relating to the registration under the Securities Act of 1933, as amended (the
"1933 Act"), of the securities of the Trust, (ii) any preliminary prospectus or
prospectus or

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supplement thereto relating to the securities of the Trust required to be filed
pursuant to the 1933 Act, and (iii) a Registration Statement on Form 8-A or
other appropriate form (the "1934 Act Registration Statement"), including all
pre-effective and post-effective amendments thereto, relating to the
registration of the securities of the Trust under the Securities Exchange Act of
1934, as amended;

         (b) if and at such time as determined by the Depositor, to file with
the or the National Association of Securities Dealers ("NASD") or the New York
Stock Exchange or other exchange, and execute on behalf of the Trust a listing
application and all other applications, statements, certificates, agreements and
other instruments as shall be necessary or desirable to cause the securities of
the Trust to be listed on the New York Stock Exchange or other exchange;

         (c) to file and execute on behalf of the Trust, such applications,
reports, surety bonds, irrevocable consents, appointments of attorney for
service of process and other papers and documents that shall be necessary or
desirable to register the securities of the Trust under the securities or "Blue
Sky" laws of such jurisdictions as the Depositor, on behalf of the Trust, may
deem necessary or desirable;

         (d) to execute and deliver letters or documents to, or instruments for
filing with, a depository relating to the securities of the Trust;

         (e) to execute, deliver and perform on behalf of the Trust an
underwriting agreement with one or more underwriters relating to the offering of
the securities of the Trust; and

         (f) to execute on behalf of the Trust such purchase agreements with one
or more purchasers or agents relating to an offering of securities of the Trust
as the Depositor, in its sole discretion on behalf of the Trust, may deem
necessary or desirable.

         In the event that any filing referred to in this Section 5 is required
by the rules and regulations of the Commission, the NASD, the New York Stock
Exchange or other exchange, or state securities or "Blue Sky" laws to be
executed on behalf of the Trust by a trustee, the Depositor may appoint
administrative trustees and any such administrative trustees, in their capacity
as trustees of the Trust, are hereby authorized to join in any such filing and
to execute on behalf of the Trust any and all of the foregoing.

         6. This Trust Agreement represents the entire agreement between the
parties hereto with respect to the subject matter hereof, and supersedes all
prior agreements and understandings between the parties, whether written or
oral.

         7. This Trust Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware, without reference to its
conflict of law provisions, and the obligations, rights and remedies of the
parties hereunder shall be determined in accordance with such laws. Sections
3540 and 3561 of Title 12 of the Delaware Code shall not apply to the Trust.

         8. This Trust Agreement may be executed in two or more counterparts,
each of which shall be an original, but all such counterparts shall together
constitute one and the same agreement.

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         9. This Trust Agreement may be amended and restated by the parties
hereto as necessary to provide for the operation of the Trust; provided,
however, that the Trustee shall not be required to enter into any amendment
hereto which adversely affects the rights, duties or immunities of the Trustee.

         10. The Trust may dissolve at the election of the Depositor. Upon
dissolution, the Trustee shall file a certificate of cancellation in accordance
with the Act and apply the funds deposited with it pursuant to Section 1(b)
above to reimburse the Trustee for any filing fees or other expenses in
connection therewith. Any remaining funds shall, after payment of any other
expenses of the Trust, be returned to the Depositor.



                            [Signature page follows]


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         IN WITNESS WHEREOF, the parties hereto have caused this Trust Agreement
to be duly executed by their respective officers hereunto duly authorized, as of
the day and year first above written.

                                       WILMINGTON TRUST COMPANY,
                                       as Trustee



                                       By:   /s/ Patricia A. Evans
                                          ------------------------------------
                                       Name:   Patricia A. Evans
                                       Title:  Assistant Vice President


                                       RLI CORP.,
                                       as Depositor



                                       By:   /s/ Joseph E. Dondanville
                                          ------------------------------------
                                       Name:   Joseph E. Dondanville
                                       Title:  Senior Vice President and
                                               Chief Financial Officer
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                                     FORM OF
                              CERTIFICATE OF TRUST
                                       OF
                               RLI CAPITAL TRUST I


         THIS Certificate of Trust of RLI Capital Trust I (the "Trust") is being
duly executed and filed by Wilmington Trust Company, a Delaware banking
corporation, as trustee, to form a statutory trust under the Delaware Statutory
Trust Act (12 DEL. C. Section 3801 ET SEQ.) (the "Act").

         1. NAME. The name of the statutory trust formed hereby is RLI Capital
Trust I.

         2. DELAWARE TRUSTEE. The name and business address of the trustee of
the Trust in the State of Delaware is Wilmington Trust Company, Rodney Square
North, 1100 North Market Street, Wilmington, Delaware 19890-0001, Attention
Corporate Trust Administration.

         3. EFFECTIVE DATE. This Certificate of Trust shall be effective upon
filing.

         IN WITNESS WHEREOF, the undersigned has executed this Certificate in
accordance with Section 3811(a) of the Act.

                                 WILMINGTON TRUST COMPANY



                                 By:
                                    ------------------------------------
                                 Name:
                                 Title: