French police and bailiffs impounded BAR's cars on the eve of first qualifying at the French Formula One Grand Prix after a court order on Thursday.
The action left drivers Jenson Button and Jacques Villeneuve in limbo, although BAR chief David Richards was confident the matter would be resolved swiftly.
BAR are being sued by Monaco production company PPGI who claim the constructor owes them a US$3 million commission for negotiating sponsoring rights.
"We've seized some equipment and impounded the cars," a police spokesman said.
"We don't exactly know the legal problem but a court will rule on the case in emergency [session] tomorrow [Friday] and decide whether the cars are allowed to race or not," he said.
Richards called the court case opportunist and said he was expecting a counter-ruling yesterday.
"A person called France Corbeil and a company called PPGI has obtained a seizure order overnight on the cars," said Richards.
"This dates back to 1998 and a verbal contract he claims he made with [former team boss] Craig Pollock. Craig disputes this and I support Craig wholeheartedly," he said.
"We never knew about this until five years afterwards when he came to speak to us three months ago about this situation. He served the order on us tonight after the court had closed, knowing that we are in court tomorrow morning at nine o'clock to have it overturned," he said.
"I'm totally confident that at nine o'clock tomorrow morning our legal team will be in court and have this matter resolved in time for first practice at 11 o'clock," he said.
BAR are fifth in the constructors' table, while Button is 10th and Villenevue 13th in the world championship drivers' standings.
Five uniformed police officers and a bailiff appeared at the BAR garages with a warrant allowing them to impound the cars.
They discussed the legal proceedings with Pasquale Lattoneddu, a close aide of Formula One supremo Bernie Ecclestone.
BAR mechanics removed the Bridgestone tires stacked in front of the trucks while journalists and photographers were kept at bay. The cars were pushed into the transporters which remained where they were parked with official seals.
"We are just abiding completely by the legal status that he has obtained," Richards told reporters outside the BAR motor home. "It's very opportunist."
The spokesman said the police had been asked to act over the same dispute that flared up at last month's Monaco Grand Prix.