The doctor-patient relationship is one of trust. So it was deeply troubling to learn last week that Dr. Reinaldo de los Heros, whose patient overdosed last year on drugs that he prescribed, will be allowed to keep practicing despite a long history of sanctions. The state medical board’s actions in this case indicate a troubling reluctance to hold doctors accountable – and to take seriously the risk to patients posed by physician misconduct.

De los Heros was sanctioned last month for failing to coordinate care with other doctors and for a lack of or incomplete notes on his treatment of Kelly Deyo, a 39-year-old Westbrook woman who struggled with mental illness and drug addiction. The Falmouth psychiatrist won’t lose his license, the Maine Board of Licensure in Medicine decided; for at least six months, however, he’ll have to be supervised by another doctor.

The Deyo case isn’t the first time that de los Heros has faced the state board. Twice in recent years – in 2009 and 2012 – the panel has raised concerns about his practice after getting complaints regarding his care. What’s more, three other states revoked his license when he was convicted of felony Medicaid fraud in 1997.

None of these issues came up when the board judged the complaint brought by Deyo’s mother, Elizabeth Marquis, after her daughter’s April 2015 suicide. That’s because to ensure due process, each case must stand on its merits, Tim Terranova, the board’s assistant executive director, told the Press Herald.

But with all due respect, there would seem to be a far simpler explanation: Physicians, like other people, are innately biased in favor of their peers and will tend to protect them, not discipline them. Seven of the 10 members of the Maine medical board are doctors (three are members of the public).

And there’s also evidence to support the idea that the board is ignoring its own red flags. In the 2012 case, the board sent de los Heros a letter that urged him to reduce the practice of prescribing multiple drugs to a single patient and warned him that “failure to heed this guidance might lead to a disciplinary proceeding.”

This same concern was also raised in connection with Kelly Deyo’s death: Her mother presented the Maine medical board with pharmacy records showing that in a matter of weeks, de los Heros had given her daughter four new prescriptions and doubled the dosage of a drug she was already taking.

Ultimately, the panel did not conclude that overprescribing was a factor in Deyo’s death. That said, the board accumulated evidence on de los Heros’ side. It allowed him to hire an expert witness, which people who bring complaints generally don’t get to do. And the board chose not to hire an independent physician to evaluate the case, though it has the authority to do that – authority that the panel frequently chooses not to exercise, said Terranova, the board official.

It’s tough to assess the performance of the medical licensing board in Maine or any other state. Several years ago, the Federation of State Medical Boards stopped issuing the data that consumer watchdogs had been using to rank state medical disciplinary practices.

But for patients, this much is clear: We share information with our doctors that we don’t share with anyone else. In return, we expect from them a credible diagnosis and safe and effective treatment. We’re unsettled by the obvious and significant shortcomings in the system that’s meant to protect us from the physicians who don’t live up to this standard – and we wonder what it will take to compel improvement.