A fomer police chief was the key player in the decision to make Christian Brueckner a formal suspect in the Madeleine McCann inquiry.
Luis Mota Carmo, 60, has taken over day-to-day control of the long-running prosecution probe in Portugal.
Days after replacing the previous lead prosecutor, he led the move to make convicted German paedophile Brueckner an “arguido” in the case.
Mr Mota Carmo persuaded bosses in Lisbon to agree to prepare the way for possible criminal charges against Brueckner – currently in prison in his home country – if German prosecutors find evidence linking him to Madeleine’s disappearance on May 3, 2007, when she was three.
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A source said: “It’s always a concern when a fresh prosecutor takes charge of a high-profile case but Luis knows this one inside out and has hit the ground running.
“The decision to make Brueckner an arguido was very much his.”
Madeleine, from Leicester, vanished while on holiday in Praia da Luz in the Algarve. Mr Mota Carmo, head of the regional prosecution service, is awaiting the results of forensic tests on the camper van Brueckner drove while living in the area at the time.
Brueckner was made an arguido after warnings from lawyers that Portugal’s 15-year limit on prosecutions of serious crimes could prevent him being prosecuted after Tuesday. The source said: “Luis wants to make sure there’s no impediment to the possibility of a prosecution here.
“But that alone is not the reason this move was made.
“Legally, there has to be a sound basis for anyone to be made an arguido, and there are multiple reasons why Brueckner is in the frame.”
The source said Brueckner could be prosecuted in Portugal or Germany.
Mr Mota Carmo ran the Judicial Police in the Algarve from 2009 to 2018. He and ex-Met police detective Andy Redwood played key roles in 2014 during the digs in Praia da Luz in the hunt for Madeleine.
Brueckner, 45, denies involvement in the disappearance. He is in jail for raping a woman in Praia da Luz in 2005.
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