Horner faced an eight-week-long probe by an independent lawyer appointed by Red Bull after claims of inappropriate behaviour were made against him by a female employee.
Following analysis of evidence at the centre of the matter, plus interviews with key figures at the team, Horner was cleared of any wrongdoing on the eve of the season-opening Bahrain Grand Prix.
A statement from Red Bull at the time said: “The independent investigation into the allegations made against Mr Horner is complete, and Red Bull can confirm that the grievance has been dismissed. The complainant has a right of appeal.”
While no further details were offered about the findings of the investigation, Autosport has learned that one of the consequences has been to take action against the employee at the centre of the matter.
It is understood that she remained employed by the Milton Keynes-based team until as recently as this week but has now been suspended.
There has been no official statement from the team about the matter, and a spokesman refused to confirm any details when approached by Autosport.
He said: “We are unable to comment as it is an internal matter.”
The decision by Red Bull to suspend the staff member adds a further twist to a storyline that has gripped F1 for recent weeks.
Though cleared by the investigation of any wrongdoing, his situation was not helped when, just 24 hours later, an anonymous source emailed alleged evidence from the case to senior F1 personnel – including team principals and media.
Horner also found himself on the receiving end of strong criticism from Jos Verstappen, father of Max, after the Bahrain GP, when the Dutchman spoke out in the media against him.
So far, Horner has not talked openly about the matter – but the public attacks on him have fuelled suspicion of a conspiracy to bring him down for unspecified reasons.
In Bahrain, Horner was shown clear support from the Thai majority owner of Red Bull, Chalerm Yoovidhya. The pair were pictured on the grid before the race and they both celebrated Verstappen's victory in parc ferme.
It is expected that Red Bull’s managing director Oliver Mintzlaff will attend this weekend’s Saudi Arabian Grand Prix, and it will be interesting to see if he chooses to comment on the matter amid speculation that there had been unease from the Austrian side of the company over the matter.
