A lawyer is obligated to protect his client's interests and to carry out his client's directions in these matters. Not doing so would violate multiple ethical rules applicable to lawyers. Some of the relevant provisions of the American Bar Association's Model Rules of Professional Conduct which are the template for every state's ethical rules (some with local variation) are:
Rule 1.2 Scope of Representation and Allocation of Authority Between Client and Lawyer
a) Subject to paragraphs (c) and (d), a lawyer shall abide by a
client's decisions concerning the objectives of representation and, as
required by Rule 1.4, shall consult with the client as to the means by
which they are to be pursued. A lawyer may take such action on
behalf of the client as is impliedly authorized to carry out the
representation. A lawyer shall abide by a client's decision whether to
settle a matter. In a criminal case, the lawyer shall abide by the
client's decision, after consultation with the lawyer, as to a plea to
be entered, whether to waive jury trial and whether the client will
testify.
(b) A lawyer's representation of a client, including representation by
appointment, does not constitute an endorsement of the client's
political, economic, social or moral views or activities.
(c) A lawyer may limit the scope of the representation if the
limitation is reasonable under the circumstances and the client gives
informed consent.
(d) A lawyer shall not counsel a client to engage, or assist a client,
in conduct that the lawyer knows is criminal or fraudulent, but a
lawyer may discuss the legal consequences of any proposed course of
conduct with a client and may counsel or assist a client to make a
good faith effort to determine the validity, scope, meaning or
application of the law.
Rule 1.7 Conflict of Interest: Current Clients
(a) Except as provided in paragraph (b), a lawyer shall not represent
a client if the representation involves a concurrent conflict of
interest. A concurrent conflict of interest exists if:
(1) the representation of one client will be directly adverse to
another client; or
(2) there is a significant risk that the representation of one or more
clients will be materially limited by the lawyer's responsibilities to
another client, a former client or a third person or by a personal
interest of the lawyer.
(b) Notwithstanding the existence of a concurrent conflict of interest
under paragraph (a), a lawyer may represent a client if:
(1) the lawyer reasonably believes that the lawyer will be able to
provide competent and diligent representation to each affected client;
(2) the representation is not prohibited by law;
(3) the representation does not involve the assertion of a claim by
one client against another client represented by the lawyer in the
same litigation or other proceeding before a tribunal; and
(4) each affected client gives informed consent, confirmed in writing.
Rule 1.13 Organization as Client
(a) A lawyer employed or retained by an organization represents the
organization acting through its duly authorized constituents.
(b) If a lawyer for an organization knows that an officer, employee or
other person associated with the organization is engaged in action,
intends to act or refuses to act in a matter related to the
representation that is a violation of a legal obligation to the
organization, or a violation of law that reasonably might be imputed
to the organization, and that is likely to result in substantial
injury to the organization, then the lawyer shall proceed as is
reasonably necessary in the best interest of the organization. Unless
the lawyer reasonably believes that it is not necessary in the best
interest of the organization to do so, the lawyer shall refer the
matter to higher authority in the organization, including, if
warranted by the circumstances to the highest authority that can act
on behalf of the organization as determined by applicable law.
(c) Except as provided in paragraph (d), if
(1) despite the lawyer's efforts in accordance with paragraph (b) the
highest authority that can act on behalf of the organization insists
upon or fails to address in a timely and appropriate manner an action,
or a refusal to act, that is clearly a violation of law, and
(2) the lawyer reasonably believes that the violation is reasonably
certain to result in substantial injury to the organization,
then the lawyer may reveal information relating to the representation
whether or not Rule 1.6 permits such disclosure, but only if and to
the extent the lawyer reasonably believes necessary to prevent
substantial injury to the organization.
(d) Paragraph (c) shall not apply with respect to information relating
to a lawyer's representation of an organization to investigate an
alleged violation of law, or to defend the organization or an officer,
employee or other constituent associated with the organization against
a claim arising out of an alleged violation of law.
(e) A lawyer who reasonably believes that he or she has been
discharged because of the lawyer's actions taken pursuant to
paragraphs (b) or (c), or who withdraws under circumstances that
require or permit the lawyer to take action under either of those
paragraphs, shall proceed as the lawyer reasonably believes necessary
to assure that the organization's highest authority is informed of the
lawyer's discharge or withdrawal.
(f) In dealing with an organization's directors, officers, employees,
members, shareholders or other constituents, a lawyer shall explain
the identity of the client when the lawyer knows or reasonably should
know that the organization's interests are adverse to those of the
constituents with whom the lawyer is dealing.
(g) A lawyer representing an organization may also represent any of
its directors, officers, employees, members, shareholders or other
constituents, subject to the provisions of Rule 1.7. If the
organization's consent to the dual representation is required by Rule
1.7, the consent shall be given by an appropriate official of the organization other than the individual who is to be represented, or by
the shareholders.
Rule 1.16 Declining or Terminating Representation
(a) Except as stated in paragraph (c), a lawyer shall not represent a
client or, where representation has commenced, shall withdraw from the
representation of a client if:
(1) the representation will result in violation of the rules of
professional conduct or other law;
(2) the lawyer's physical or mental condition materially impairs the
lawyer's ability to represent the client; or
(3) the lawyer is discharged.
(b) Except as stated in paragraph (c), a lawyer may withdraw from
representing a client if:
(1) withdrawal can be accomplished without material adverse effect on
the interests of the client;
(2) the client persists in a course of action involving the lawyer's
services that the lawyer reasonably believes is criminal or
fraudulent;
(3) the client has used the lawyer's services to perpetrate a crime or
fraud;
(4) the client insists upon taking action that the lawyer considers
repugnant or with which the lawyer has a fundamental disagreement;
(5) the client fails substantially to fulfill an obligation to the
lawyer regarding the lawyer's services and has been given reasonable
warning that the lawyer will withdraw unless the obligation is
fulfilled;
(6) the representation will result in an unreasonable financial burden
on the lawyer or has been rendered unreasonably difficult by the
client; or
(7) other good cause for withdrawal exists.
(c) A lawyer must comply with applicable law requiring notice to or
permission of a tribunal when terminating a representation. When
ordered to do so by a tribunal, a lawyer shall continue representation
notwithstanding good cause for terminating the representation.
(d) Upon termination of representation, a lawyer shall take steps to
the extent reasonably practicable to protect a client's interests,
such as giving reasonable notice to the client, allowing time for
employment of other counsel, surrendering papers and property to which
the client is entitled and refunding any advance payment of fee or
expense that has not been earned or incurred. The lawyer may retain
papers relating to the client to the extent permitted by other law.
Rule 2.1 Advisor
In representing a client, a lawyer shall exercise independent
professional judgment and render candid advice. In rendering advice, a
lawyer may refer not only to law but to other considerations such as
moral, economic, social and political factors, that may be relevant to
the client's situation.
A lawyer is certainly within his rights, and indeed his duty, to inform a client that his proposed course of action is unwise, and can withdraw from representing the client. But, in general, in a transactional matter, unless the proposed conduct constitutes a crime or fraud, the lawyer may not defy a client's directions.
Of course, while there are general rules in the law, there are also almost always fact specific exceptions to those rules.
For example, while ordinarily, writing a tough contract when dealing with a minority counterparty would not be a crime or fraud. But, if an easy contract was used with all non-minority counterparties, but not with minority counterparties and the client's instruction was intended to discriminate on the basis of race, it might very well be unlawful or even a crime, in some circumstances to do so, which would alter the lawyer's obligations.
Even then, however, a lawyer would almost never be authorized to affirmatively draft a contract contrary to the client's instructions as opposed with declining to do that work at all.