Difficult ethical issues are inherent in medical research, especially clinical trials involving human subjects. Research holds the promise of finding lifesaving treatments, but it sometimes depends on the participation of vulnerable patients suffering from serious illnesses.

We at the University of Minnesota take seriously our responsibility to patients participating in clinical studies, and our critics are wrong when they assert that we have turned a blind eye to our ethical obligations ("Medical research: Honor code still needs strengthening," a May 27 commentary by U Prof. Carl Elliott).

Let me be clear about Dan Markingson's 2004 death by suicide, which is at the center of much of this conversation. The events have been the subject of many proceedings, including two reviews by the U.S. Food and Drug Administration (2005 and 2015), a lawsuit in Hennepin County District Court (2008), complaints to the Minnesota Board of Medical Practice against two doctors (2009 and 2010), and a review by the legislative auditor (2015).

As the legislative auditor concluded, we can never know if Markingson's tragic death was the result of a clinical study conducted at 26 sites, including the University of Minnesota. However, it is clear we could have done better in our response to the concerns raised about these events. I have apologized to Dan Markingson's mother, to a legislative committee and at public forums.

In addition to recognizing and respecting the personal grief of those closest to Mr. Markingson, I believe the most meaningful way for an institution to apologize to the broader Minnesota public is to be better in the future. That is what we are doing as we move forward. The university, the nation's ninth-most-active public research university, is implementing far-reaching reforms to our human subjects protection program. Our goal is to be a national model, both ethically and operationally. Last week, a faculty-led implementation team produced a 68-page action plan (http://tinyurl.com/l735b3s) to achieve this goal.

This plan reinforces our commitment to an ethical culture, minimizes conflicts of interest, creates more robust institutional review boards and oversight, and vastly improves our approach to research involving people who have impaired decisionmaking capacity.

Dr. Steven Miles, a nationally recognized University of Minnesota bioethicist and a member of the team that wrote the report, called this plan "Markingson's legacy" and said he hopes the plan will be a national model. "Having taught medical ethics now for 34 years, I think … this is possibly the most robust policy I've ever seen," he said.

I intend to implement this plan fully and with complete transparency, and I encourage you to watch us closely and judge us fairly as we do our work.

When I came to the university in 2011, I reviewed the concerns that some had raised about the Markingson case. I also reviewed investigations of his death from the U.S. Food and Drug Administration, the Board of Medical Practice and the courts. Those are the independent bodies responsible for finding facts and resolving issues in matters such as this, and all of them have affirmed our compliance with laws and regulations.

To their credit, our university faculty wanted further assurance that our current program was at the highest levels of ethics and science, and in December 2013 the Faculty Senate requested an independent external evaluation of our human subjects protection program.

The Board of Regents and I strongly endorsed that recommendation and took immediate action. The panel's proposals for reform and improvement were so thorough and far-reaching that this spring when the Legislative Auditor issued his review, he adopted the panel's recommendations in their entirety.

I came to the University of Minnesota less than four years ago, becoming president at a time of enormous change and challenges for all postsecondary institutions. On many fronts, great progress has been made. We renewed our partnership with the state of Minnesota; tuition increases have been reined in; graduation rates are at an all-time high; administrative costs have been reduced substantially, and the quality of much of what we do has been enhanced.

But Minnesotans rightly hold everything done under the name of the "University of Minnesota" to the highest standards of excellence. Minnesotans know that even before there was a state of Minnesota, there was a University of Minnesota. Pride in the university's legacy and in its importance to all Minnesotans runs deep. I take that very seriously.

Critics are important voices, but there comes a point at which criticism of past actions stops being a catalyst for reform and, instead, becomes a barrier to necessary change in the future. We can't change the past, but with vigilance, dedication and integrity, we will move forward.

I promise all Minnesotans, our faculty and students, and our future patients and their families that the University of Minnesota's human subjects research program will soon be a model for other universities.

Eric W. Kaler is president of the University of Minnesota.