Even as Melgen cultivated a political profile in the U.S., he was never gone long from his homeland.
Fernandez, the ex-Dominican president, named him as an alternate delegate to the United Nations during his first term and an ambassador assigned to the Foreign Ministry in his second.
Meanwhile, a private plane owned by Melgen's company, DRM Med Assist LLC, made more than 100 trips to the Dominican Republic since July 2009, an Associated Press review of flight records found. Nearly a dozen of those trips showed brief stopovers at Washington, D.C.-area airports, although it's unclear who was on board because Federal Aviation Administration rules don't require private aircraft to file flight manifests.
Menendez repaid Melgen $58,500 for two 2010 trips he characterized as personal. The reimbursement was made Jan. 4 in response to the ethics complaint, but there was no public disclosure of it until this week. The reimbursement is significant for a politician who's not wealthy by Washington standards. Disclosure forms show Menendez's net worth as less than $700,000.
Whether Melgen's access or checkbook brought him any influence remains unclear.
In 2007, Menendez introduced a Senate bill, "The Glaucoma Screening Act," that proposed $10 million in grants to firms that would have in part expanded eligibility to Hispanics who are at risk of glaucoma. Melgen's clinic was not specifically cited in the bill and whether he would have benefited is not clear.
Menendez's spokeswoman Tricia Enright noted he had a long history of working with the Friends of the Congressional Glaucoma Caucus, whose leader asked the senator's staff to introduce the bill. Regardless, the legislation never made it out of committee.
The senator appeared to have weighed in on behalf of one of Melgen's companies last July during a Senate hearing, complaining about several instances where Latin American governments did not honor obligations with businesses. Menendez pressed two Obama administration officials about an unidentified company that provided cargo screening services at Dominican Republic ports.
Media reports in the Dominican Republic have highlighted a contract feud between the country's government and a port security firm, I.C.S.S.I.
The company was hired to provide X-ray screening at Dominican ports starting in 2002, according to a 2003 document reviewed by the AP. In recent years, the Dominican government had begun to balk at continuing the contract, citing concerns about high costs.
In 2011, I.C.S.S.I. was bought by a Florida firm, Border Security Services LLC, which records show is managed by Melgen. The New York Times reported Friday the port contract could be worth as much as $50 million a year.
More details inevitably will spill out as both Melgen and Menendez become tangled in an investigation. The Senate Ethics Committee is looking into whether Menendez accepted inappropriate gifts from Melgen and FBI agents carted away evidence seized from Melgen's offices, but refused to say why.
"The government has not informed Dr. Melgen what concerns it may have," said his attorney, Lawrence Duffy. "We are confident that Dr. Melgen has acted appropriately at all times."
Contributing to this report were Associated Press writers Jack Gillum, Stephen Braun and Henry Jackson in Washington; Curt Anderson in Miami; and Ezequiel Abiu Lopez in Santo Domingo, Dominican Republic.
Contact the Washington investigative team at DCinvestigations (at) ap.org.