An inquest into the deaths of serial killer Stephen Port's victims will examine whether "prejudice" or "lack of understanding" of their sexuality affected the initial Metropolitan Police investigations.
Port, now aged 44, drugged and raped four young gay men and dumped their bodies near his home in Barking, east London, between 2014 and 2015.
Following a trial at the Old Bailey, he was handed a whole life sentence for the murders of fashion student Anthony Walgate, 23, Gabriel Kovari, 22, Kent chef Daniel Whitworth, 21, and Jack Taylor, 25, a forklift truck driver from Dagenham.
A full inquest due next year is expected to focus on possible failings by police after the victims' families questioned why Port was not stopped sooner.
Andrew O'Connor QC, counsel for the coroner, told a pre-inquest hearing at the Old Bailey that the provisional scope would cover whether prejudice of officers led to failings.
Mr O'Connor said that "the most important question" for the coroner to decide was whether police treating Mr Kovari's death as non-suspicious "was a failing and led to other deaths".
He told the court: "Everyone agrees one of the core issues is whether the police investigations into the four deaths were affected by prejudice of the sexuality of Mr Walgate, Mr Kovari, Mr Whitworth and Mr Taylor and indeed Mr Port."
The lawyer said that the inquest would not stop at examining individual officers if the evidence led to institutional prejudice.
He said: "The investigation will not stop at establishing whether individual officers were biased, it will clearly need to go further than that."
He said the inquest would be making disclosure requests for any material relating to "these institutional issues".
Leslie Thomas QC, for victims' families, called for the coroner to confirm she would call a jury for the full inquest.
He said: "Arguably there is a lot the police could and should have done."We say when you look at the test, you will be driven to the inevitable conclusion that a jury should be empanelled."
Judge Sarah Munro QC, sitting as assistant coroner for East London, said: "I have concluded that I do have a reason to suspect that the deaths resulted from the acts or omissions of police or police officers. There must be a jury inquest."