Karen Shakerdge

An OB-GYN named Thomas J. Byrne was stripped of his New York medical license in 1991 for what the health department called gross negligence, among other charges. For his former patients and their families, the restoration of his license in the state stirs up feeling of anger and betrayal.

Patient safety experts are concerned that loopholes in the federal system for physician oversight allow some doctors with questionable track records to avoid further scrutiny.

Dr. Thomas J. Byrne was stripped of medical license in New York in 1991. Records show the Oklahoma medical board initially denied him a license to practice. Months later, it reversed that decision.

A New York state investigation in the 1990s found that 11 patients, including five newborns, had been harmed while under the care of an OB-GYN named Thomas J. Byrne. Health officials revoked his license. How was he able to keep practicing elsewhere?

Part 1 of Imminent Danger, a five-part investigative series, examines the track record of one OB-GYN across several states and what it says about how doctors are vetted before being allowed to see patients.