The naval police would have had “no hesitation” in investigating any possible military involvement in the sinking of a French fishing vessel “had the evidence pointed that way”, an inquest has heard.
All five French crewmen lost their lives when the Bugaled Breizh went down very suddenly in favourable conditions off the Lizard Peninsula on January 15 2004.
The question of whether a submarine may have become entangled in the Bugaled Breizh’s trawler gear and caused it to capsize has been raised repeatedly since it sank.
An inquest at London’s High Court heard on Wednesday that the Royal Navy Police Special Investigation Branch (RNPSIB) would not have been blocked from investigating the potential involvement of British combat vessels.
Andrew Billings, a former commander who led the RNPSIB team investigating the sinking in co-operation with the French authorities, said he had found no evidence any submarine of any flag was within five nautical miles of the trawler.
He told the inquest he had been confined to investigating British involvement, but would have escalated concerns about foreign vessels if he had had any.
Mr Billings continued: “Had I had any suspicion that they were involved in any way or had proof, more importantly, I would have most certainly raised that as a credible issue and raised it up through the chain of command and then obviously taken advice from there.”
“I found nothing that would have made me alarmed at what I’d found and no evidence pointing towards any foreign involvement,” he said.
When asked by Judge Nigel Lickley QC what he would have done if there had been some military involvement, he said: “We would have investigated it. You know it’s not unheard of – we’ve investigated many incidents involving submarines.”
Mr Billings cited the deaths of two sailors aboard HMS Tireless in 2007.
“We investigated that over a number of years to draw a successful conclusion for the families,” he said.
“We would have had no hesitation but to do the same thing in this instance had the evidence pointed that way.”
The inquest is only considering the deaths of skipper Yves Marie Gloaguen, 45, and Pascal Lucien Le Floch, 49.
It means that under English law an inquest must be held here.
The body of a third man, Patrick Gloaguen, 35, was recovered during a salvage but was taken to France, while the bodies of Georges Lemetayer, 60, and Eric Guillamet, 42, were never found.
As a result, their deaths are not the subject of the inquest, although their families are taking part in the process.
A senior naval officer previously told the inquest it would be “unthinkable” for a British or allied submarine crew to falsify records about a vessel’s location.
Commander Daniel Simmonds is currently in charge of daily operations of all UK submarines and Nato submarines that come under British operation and control.
When asked what the consequences would be for anyone found to have falsified logs or other records, Cdr Simmonds replied: “It would erode trust at the highest level.”
He told the court: “My answer would be very simple. Whilst I’ve never known it to happen, because it’s just unthinkable, the ramifications would be significant and would absolutely erode the trust at the highest levels between allied partners.”
The inquest also heard the Royal Navy is “very confident” there were no non-allied submarines within 50 nautical miles of the Bugaled Breizh when it sank.
A Dutch submarine, the Dolfijn, is believed to have been the closest submarine, and was 12 nautical miles south of the Bugaled Breizh when it sank.
The inquest, which is scheduled to run until October 22, continues.