Wednesday, 20 March 2019 10:15

Privacy, Litigation Fairness and Big Tobacco Access to Anonymized Health Data

Written by  Teresa Scassa
Rate this item
(0 votes)

Ongoing litigation in Canada over the recovery by provincial governments of health care costs related to tobacco use continues to raise interesting issues about the intersection of privacy, civil procedure, and big data analytics. A March 7 2019 decision by the New Brunswick Court of Queen’s Bench (Her Majesty the Queen v. Rothmans Inc.) picks up the threads left hanging by the rather muted decision of the Supreme Court of Canada in The Queen v. Philip Morris International Inc.

The litigation before the Supreme Court of Canada arose from the BC government’s attempt to recover tobacco-related health care costs in that province. The central issue concerned the degree of access to be provided to one of the big tobacco defendants, Philip Morris International (PMI), to the databases relied upon by the province to calculate tobacco-related health care costs. PMI wanted access to the databases in order to develop its own experts’ opinions on the nature and extent of these costs, and to challenge the opinions to be provided by provincial experts who would have full access to the databases. Although the databases contained aggregate, de-identified data, the government denied access, citing the privacy interests of British Columbians in their health care data. As a compromise, they offered limited and supervised access to the databases at Statistics Canada Research Data Centre. While the other tobacco company defendants accepted this compromise, PMI did not, and sought a court order granting it full access.

The Supreme Court of Canada’s decision was a narrow one. It interpreted the applicable legislation as making health care records and documents of individuals non-compellable in litigation for recovery of costs based on aggregate health care data. The Court considered the health databases to be “records” and “documents” and therefore not compellable. However, their decision touched only on the issue of whether PMI was entitled to access the databases to allow its own experts to prepare opinions. The Court did not address whether a defendant would be entitled to access the databases in order to challenge the plaintiff’s expert’s report that was created using the database information. Justice Brown, who wrote for the unanimous Court stated: “To be clear, the databases will be compellable once "relied on by an expert witness": s. 2(5)(b). A "statistically meaningful sample" of the databases, once anonymized, may also be compelled on a successful application under ss. 2(5)(d) and 2(5) (e).” (at para 36) In response to concerns about trial fairness, Justice Brown noted the early stage of the litigation, and stated that: “Within the Act, the Legislature has provided a number of mechanisms through which trial fairness may be preserved. Specifically, s. 2(5)(b) itself requires that any document relied upon by an expert witness be produced.” (at para 34) He also observed that:

 

[Section] 2(5)(d) permits a court, on application, to order discovery of a "statistically meaningful sample" of any of the records and documents that are otherwise protected by s. 2(5)(b). No defendant has yet made such an application and thus no court has yet had reason to consider what would constitute a "statistically meaningful sample" of the protected documents. (at para 35)

The Supreme Court of Canada therefore essentially laid the groundwork for the motions brought to the New Brunswick Court of Queen’s Bench under essentially similar legislation. Section 2 of New Brunswick’s Tobacco Damages and Health Care Costs Recovery Act is more or less identical to the provisions considered by the Supreme Court of Canada. Sections 2(5)(d) and (e) of the Act provide:

2(5). . .

(b) the health care records and documents of particular individual insured persons or the documents relating to the provision of health care benefits for particular individual insured persons are not compellable except as provided under a rule of law, practice or procedure that requires the production of documents relied on by an expert witness,

. . .

(d) notwithstanding paragraphs (b) and (c), on application by a defendant, the court may order discovery of a statistically meaningful sample of the documents referred to in paragraph (b) and the order shall include directions concerning the nature, level of detail and type of information to be disclosed, and

(e) if an order is made under paragraph (d), the identity of particular individual insured persons shall not be disclosed and all identifiers that disclose or may be used to trace the names or identities of any particular individual insured persons shall be deleted from any documents before the documents are disclosed.

Thus, the provisions allow for discovery of documents relied upon by the government, subject to an obligation to deidentify them.

An expert witness for the Province of New Brunswick had produced several reports relying on provincial health care data. The province maintained that for privacy reasons the defendant should not have direct access to the data, even though it was deidentified in the database. It offered instead to provide recourse through a Statistics Canada Research Data Centre. The defendant sought “a "statistically meaningful sample" of clinical health care records concerning 1,273 individual insured persons in New Brunswick, under the authority of subsections 2(5)(d) and (e) of the Act.” (at para 2) It also sought a production order for “all Provincial administrative databases and national survey data” that was relied upon by the Province’s expert witness in preparing his reports. In addition, they sought access to data from other provincial health databases that were not relied upon by the expert in his report – the defendant was interested in assessing the approaches he chose not to pursue in addition to those he actually pursued. The province argued that it had provided sufficient access to relevant data through the Statistics Canada RDC, which implemented appropriate safeguards to protect privacy.

Justice Petrie first considered whether the access via Statistics Canada was adequate and he concluded that it was not. He noted that one of the other defendants in the litigation had filed an access to information request with Statistics Canada and had thereby learned of some of the work carried out by the province’s expert witness, including some “calculations and analysis” that he had chosen not to rely upon in his work. While the defendants were not prejudiced by this disclosure, they used it as an example of a flaw in the system administered by Stats Canada since its obligations under the Access to Information Act had led to the disclosure of confidential and privileged information. They argued that they could be prejudiced in their own work through Stats Canada by access to information requests from any number of entities with interests adverse to theirs, including other provincial governments. Justice Petrie sided with the defendants. He found that: “the Province's production of the data and materials relied upon by Dr. Harrison only within the confines and authority of a third party to this litigation, StatsCan/RDC poses a real risk to the confidentiality and privilege that must be accorded to the defendants and their experts.” (at para 66) He also stated:

 

The risk of potential premature or inadvertent disclosure, as determined by StatsCan, presents an unfair obstacle to the defendants' experts if required to undertake their analysis only within StatsCan/RDC. In short, the StatsCan Agreement terms and conditions are overly restrictive and likely pose a serious risk to trial fairness. I am of the view that less restrictive options are available to the Court and ones that more fairly balance trial fairness with the risks to any privacy breach for individual New Brunswickers. (at para 65)

These less restrictive options stem from the Courts own power to “provide for directions on production and to protect the personal and sensitive information of individuals.” (at para 68) Justice Petrie found that “there are no applicable restrictions under privacy legislation to prohibit the Court from ordering document production outside of the StatsCan/RDC in the circumstances.” (at para 72) He rejected arguments that the Statistics Act prevented such disclosures, ruling that custody and control over the health data remained shared between the province and Stats Canada, and that the court could order the province to disclose it. Further, it found:

 

Where, as here, the Province has served the defendants with five expert reports of Dr. Harrison and indicated their intention to call him as a witness at trial, I find that subsection 2(5)(b) of the Act expressly requires production of the materials "relied upon" by the expert in the ordinary course. I am confident that the Court is capable of fashioning an order which would adequately address any privacy or reidentification concerns while, at the same time, imposing more balanced measures on the defendants and/or their experts. (at para 82)

These measures could include a direction by the court that no party attempt to identify specific individuals from the deidentified data.

On the issue of the disclosure of a statistically significant sample of health records, the defendant sought a sample from over 1200 New Brunswick patients. The legislation specifically provides in s. 2(5)(d) that a court may order discovery of a statistically meaningful sample of the documents”, so long as they are deidentified. Justice Petrie found that there was a statutory basis for making this order, so long as privacy could be preserved. He rejected the province’s argument that the only way to do this was through the Stats Canada RDC. Instead, he relied upon the court’s own powers to tailor orders to the circumstances. He stated: “I am of the view that there is a satisfactory alternative to the StatsCan/RDC Agreement on terms that can allow for any re-identification risks to be properly addressed by way of a consent order preferably, and if not, by way of further submissions and ruling of this Court.” (at para 131)

On the issue of privacy and the deidentified records in the statistically significant sample, Justice Petrie stated:

 

Even if individuals might be able to be re-identified, which I am not convinced, it is not clear why the defendants would ever do so. [. . .] With respect to this request for an individual's personal health records, the Province has suggested no other alternative to such a sample, nor any alternative to the suggested approach on "anonymization" of the information. (at para 141)

He granted the orders requested by the defendants and required the parties to come to terms on a consent order to protect privacy in a manner consistent with his reasons.

This decision raises issues that are more interesting than those that were before the Supreme Court of Canada, mainly because the court is required in this case to specifically address the balance between privacy and fairness in litigation. The relevant legislation clearly does not require defendants to accept the plaintiff’s analyses of health data at face value; they are entitled to conduct their own analyses to test the plaintiff’s evidence, and they are permitted to do so using the data directly and not through some intermediary. While this means that sensitive health data, although anonymized, will be in the hands of the defendant tobacco companies, the court is confident that the rules of the litigation process, including the implied undertaking rule and the power of the court to set limits on parties’ conduct will be sufficient to protect privacy. Although this court seems to believe that reidentification is not likely to be possible (a view that is certainly open to challenge), even if it were possible, direction from the court that no analyses designed to permit identification will take place, is considered sufficient.

Teresa Scassa

Latest from Teresa Scassa

Related items (by tag)

back to top