Canada: The Expert Witness And Environmental Law Practical And Ethical Considerations For Lawyers


The complex nature of environmental issues that come across a lawyer's desk often require highly technical expertise from any (or all) of a number of highly specialized disciplines. Expertise could be needed from fields that include geology; hydrology; hydrogeology, engineering, organic and inorganic chemistry, toxicology, epidemiology and even meteorology. That list is by no means meant to be exhaustive.

Equally varied is the context in which the lawyer might need such expertise. While one most commonly thinks of an environmental expert in their role as expert witness at trial, in reality an environmental expert serves many essential roles in both litigation and transactional legal work. These roles include litigation advisor, assisting with due diligence in a transaction, assisting with identifying risks that might need to be specifically allocated in an agreement, determination of costs for remediation or risk management measures, perhaps in the context of an escrow agreement or a holdback to secure a remediation obligation and as an aid to planning, coordinating and scheduling projects. An expert might even be required to generate a final report on which the satisfaction of a contractual obligation might depend.

At the same time, working with the expert must be done in a way that not only furthers the client's interest but complies with the ethical obligations of the lawyer, as well as any professional body to which the expert belongs.

Working effectively with environmental experts is in fact an essential day to day skill of any environmental lawyer. In this paper, I will touch on some of the ethical, scientific and legal issues that arise when lawyers work with environmental experts. I will also address some specific issues that arise in the context of preparing a consultant for a hearing. However, my hope is that it will be seen that preparing an environmental expert for any role that might be needed by a lawyer, is going to require many overlapping considerations regardless of the ultimate role.

Setting the scene: What are the questions an environmental expert is likely to be asked?

Typical questions include:

Is the land contaminated?

With what?

To what extent?

What does "contaminated" mean?

To what standard?

Does the contamination restrict my use of the property?

Is it hazardous?

Where did it come from?

Where is it going?

What can I do about it?

What are my options?

How much will it cost?

How long will it take?

How sure are you of your answers?


When does the lawyer need an environmental expert?

The Law Society's Rules of Conduct provide a useful starting point, in particular Rule 3.1 "Competence":

3.1-2 A lawyer shall perform any legal services undertaken on a client's behalf to the standard of a competent lawyer

Paragraph 7 of the commentary provides further elaboration and specifically points to an ethical obligation to recognize when scientific expertise may be needed:

[7] The lawyer should also recognize that competence for a particular task may require seeking advice from or collaborating with experts in scientific, accounting, or other non-legal fields, and, in such a situation, when it is appropriate, the lawyer should not hesitate to seek the client's instructions to consult experts.

The scope of this rule applies to far more than just trial preparation of course. It means a real estate lawyer might have a duty to advise a client that an environmental expert may be needed to assess whether there are any environmental risks associated with a proposed real estate transaction. In a legal landscape where courts and legislators hold an owner or previous owner of contaminated land responsible for the impact of contamination regardless of fault (see Kawartha Lakes (City) v. Ontario (Environment), 2013 ONCA 310 (CanLII)); where liability could be unlimited and could extend to officers and directors personally (see Baker v. Ministry of the Environment, 2013 ONSC 414) and in the context of ever more rigorous environmental standards and changing scientific information, what lawyer can confidently say they can competently advise a client on the risks of any transaction involving potentially contaminated land, without at least conducting a Phase I and if recommended, a Phase II investigation?

The same considerations of course apply equally to a lawyer advising on the purchase or sale of a business, financing or virtually any transaction involving land. Should a lawyer advise a charity on whether to accept a gift of land without obtaining some expert environmental advice? What about an estates lawyer advising a testator or a beneficiary about the value of a proposed gift of land or the potential liability attached to it?

While it is routine on almost every business transaction to consider the tax implications and obtain expert advice when needed, lawyers must now face the reality that environmental issues and liability concerns permeate virtually every commercial transaction for which legal advice is needed. The Rules of Conduct are clear. It is the ethical duty of every lawyer to realize when environmental expert advice is needed and to seek the client's instructions to consult such experts.

Considerations when hiring a consultant

How does one pick the right consultant? Previous experience working with the expert or their firm is often a starting point. Other lawyers specializing in the area can often be a good source of referrals. Online tools have made the task much easier than it used to be. Ultimately, there is no substitute for a face to face meeting to assess the suitability of the proposed expert, especially if there is a possibility they may be needed to testify in court at some point. If the expert seems to be acceptable, a formal retainer letter should be prepared. Beyond ensuring the consultant has the requisite expertise, the letter retaining the consultant should address certain basic points such as

Confirm the consultant has checked for and advised of any actual or potential conflicts.

Be as specific as possible as to what questions are being asked.

Will the report be prepared under privilege or is it meant to be disclosed to third parties?

Information provided to or obtained by the consultant should be treated as confidential by the consultant.

Contact with third parties, including Regulators may need to be discussed in advance.

Should drafts be provided first?

Will reliance letters be provided if needed?

The consultant will likely have their own agreement form. It is important to check the consultant' s contract for limitations on liability. Liability should not be limited to the value of the retainer. It should match at least the terms of their insurance policy and those limits should be disclosed. If the retainer is based on a fee estimate, do make sure the client knows that the process is often iterative – one set of boreholes may lead to questions requiring more. The initial work proposed may simply not be enough to provide the answers required.

The lawyer should be aware of their own potential for conflict of interest. If the client asks the lawyer to recommend a consultant, what should the lawyer do? Is the consultant a source of referral work for the lawyer? Should that be disclosed to the client? What if the client has a preferred consultant, but they do not happen to be one of the lawyer's top choices for the particular task? Should the lawyer say something or remain silent? Both the lawyer and client could be working with the consultant for a long time. Any report they provide can have long lasting implications. It is essential that these questions be thought through carefully before hiring the consultant.

Is the retainer letter producible?

If an expert is hired for the purpose of providing an opinion to be used in litigation, is the retainer letter producible pursuant to Rule 53 of the Rules of Civil Procedure? There is some caselaw to the effect that it is not. In Maxrelco Immeubles Inc. v. Jim Pattison Industries Ltd. 2017 ONSC 5836, the court held that there was no obligation to produce the instructing letter unless there was a basis to support a suspicion of improper influence and that Rule 53.03(2.1)3 was satisfied when the information required by that Rule was set out in the expert report itself:

[37] I have not been provided with any evidence to support that counsel for Maxrelco acted inappropriately with the expert witness. There is no foundation to support a reasonable suspicion that counsel improperly influenced the reports. Lumipro should not be provided with the interactions between counsel and the expert witness.

[38] In addition, the provision in Rule 53.03(2.1)(3) of the Rules has been met by Maxrelco since it provided the required information in the Introduction of the two expert reports. Lastly, based on the facts of this cases and considering the applicable case law, I find that the retention letters remain covered by litigation privilege. Consequently, Maxrelco is not required to produce to Lumipro the instruction letters sent to the expert witness.

Nevertheless, a properly drafted retainer letter can provide useful evidence of the impartiality of the witness and the fairness of the instructions given to them. Because of the risk the retainer letter may be produced to the other side, even greater care must be exercised to ensure the letter contains no confidential information that is not absolutely necessary for the consultant to render their opinion.

The duty of confidentiality

Section 3.3-1 of the Law Society Rules provides that:

3.3-1 A lawyer at all times shall hold in strict confidence all information concerning the business and affairs of the client acquired in the course of the professional relationship and shall not divulge any such information unless

(a) expressly or impliedly authorized by the client;

(b) required by law or by order of a tribunal of competent jurisdiction to do so;

(c) required to provide the information to the Law Society; or

(d) otherwise permitted by rules 3.3-2 to 3.3-6.

Practically speaking this means that care must be taken to ensure the consultant is provided with enough information in order to allow them provide a useful opinion while minimizing the disclosure of any confidential information that is not necessary for them to do their job. At the same time, the lawyer must be cautious to not omit any material information that may jeopardize the validity of the expert's findings. If possible the client should be an active participant in this process as the exercise may well trigger recollections of additional facts or previously forgotten documents.

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