Brailsford is so concerned that he has consulted lawyers over the breach. Froome was repeatedly questioned during the 2013 Tour, which he won, about his performances and attitude to doping.
The 30-year-old Team Sky leader has always insisted he competes clean and before this year’s race described “clowns” interpreting power data as “unhelpful”. Froome led this year’s race by 12 seconds before Tuesday’s 10th stage and Brailsford, the Team Sky principal, was asked if he was ready for a repeat of the doping questions.
“It’s part of the game, isn’t it? If he does well [on Tuesday], the rest of the Tour it’s ‘How do you know he’s not doping?’
“The question of how to prove a negative is always going to be a difficult one. We think someone has hacked into our training data and got Chris’s files, so we’ve got some legal guys on the case there.
“I would never mention a name [but] ethically and morally, if you are going to accuse someone of doping, then don’t cheat.”
Brailsford said: “I used to worry about it a lot more but I don’t any more. It’s part of the game. Just try to be honest, tell the truth, be open.” Team Sky tightly controls access to riders’ data, which can be skewed and does not account for all variables.
The team was under surveillance on Sunday night by photographers hoping to catch Froome going to sleep in Brailsford’s motorhome in Pau.
The former British Cycling performance director has brought his personal motorhome to the Tour, giving him a base to work and allowing him to sleep in the same environment every night.
Brailsford had hoped Froome would benefit from using a campervan in the same way at the Tour but the UCI amended its rules after Team Sky used one for Richie Porte at the Giro d’Italia.
The regulations were subsequently amended to dictate that riders must stay in the assigned hotels, which range in standard.
Organisers ensure teams are given fair hotel allocation across the three-week race, with teams in five-star accommodation one night and budget hotels the next.
Brailsford argues a good night’s sleep is essential for any athlete and minimum standards of accommodation should be in place.
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