Suspicions that contents of the HIV Registry had been leaked emerged as early as in 2012, when American fraudster Mikhy Farrera Brochez blew the whistle on his Singaporean doctor-boyfriend Ler Teck Siang to the Ministry of Health (MOH).
Brochez complained to an MOH director that Ler had shared screenshots of the HIV Registry - which the doctor had access to as the head of the National Public Health Unit - and told another individual that he was HIV-positive.
The complaint led to MOH launching a probe into Ler while the Ministry of Manpower (MOM) investigated whether Brochez was really HIV-free, as stated in his Employment Pass (EP) application.
These details emerged in evidence and testimonies in court papers involving the two when they were dealt with on charges of cheating and lying to public servants, among other charges.
Ler and Brochez are now at the centre of another high-profile data breach in the healthcare sector that came to light on Monday.
MOH revealed that more than 14,200 people with the human immunodeficiency virus had their confidential information, including contact details and medical information, leaked online by Brochez.
Ler, 36, has been charged with failing to retain possession of a thumbdrive containing information from the HIV Registry.
Ler was sentenced last September to two years in jail and is appealing against his conviction and sentence. The prosecution dropped its appeal against his sentence.
Brochez, 34, was sentenced in March 2017 to 28 months in jail, and was deported in April last year after completing his sentence.
Ler told the police that he and Brochez had problems in their relationship in early 2009.
The two became acquainted through a gay dating website and met in person for the first time in Hong Kong in 2007. By January the next year, Brochez had moved to Singapore and was living with Ler in his Craig Road apartment.
Ler said that Brochez had accused him of sharing a screenshot of the HIV Registry with another individual and telling him that Brochez was HIV-positive.
He added that some time towards the end of 2012, he was asked by Dr Jeffrey Cutter - then director of the Communicable Diseases Division at MOH - about Brochez's allegations against him. Specifically, Dr Cutter had asked Ler if he had taken screenshots of the HIV Registry.
"Following this, the accused (Ler) was informed of an official investigation by MOH in respect of the allegations made by Mikhy against him," said court papers.
In September 2013, Ler was contacted by an officer from MOH's Surveillance and Enforcement Branch (SEB).
Around Oct 4 that year, MOM received information from MOH that Brochez was HIV-positive and might have made a false declaration in his application in 2011 for a Personalised Employment Pass (PEP).
MOM informed Brochez about the tip-off it had received and instructed him on Oct 8 to cancel his PEP by Nov 8, failing which the ministry would cancel it.
But Brochez replied that he would supply "proof of being free of HIV" to MOM.
On Nov 22, 2013, he went to a clinic where Ler was working as a locum. Ler passed off his own blood as Brochez's, which enabled the American to retain his PEP.
It was the same ruse the two had used when Brochez first applied for an EP in 2008.
But the MOH investigator was surprised to find out that it was Ler who had conducted the test on Brochez when he visited the clinic as part of his investigations.
On Dec 10, 2013, Ler was questioned by the same SEB officer at Kranji Camp, where the doctor was on in-camp training duty.
Ler then lied that the blood was not taken from "Mikhy", who had accused him of leaking his HIV-positive status, but from another person. He was later convicted of lying to a public servant.
The SEB officer informed his superiors. A day later, a police report was lodged over a possible cheating offence over the blood test.
On Jan 23, 2014, Ler was questioned by the police and he lied again that it was Brochez's blood - and not his own - that was tested on Nov 22.
MOH said Ler resigned in January 2014.
On May 2, 2014, Brochez also lied to the police that it was his blood that was tested during the HIV test.
• Additional reporting by Fabian Koh and Rei Kurohi
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