A Nevada court has ruled FBI agents can dress up as ISP repairmen to blag their way into a suspect's home without a search warrant – but must tell the courts about it when they do.

The ruling stems from a case brought by the Feds against Malaysian poker player Wei Seng Phua and his son, whom the agency accused of running an illegal betting syndicate from a luxury Las Vegas villa during last year's FIFA World Cup.

The duo hired the house in the grounds of Caesars Palace casino on the famous Strip, and asked for large-screen monitors, laptops, and extra internet broadband lines to be installed for the duration of their stay. This raised suspicion among the staff, and the FBI were called in.

The Feds couldn't get a search warrant based on the information they had, so hatched a cunning plan to get inside the property. With the hotel's connivance, they cut internet access to the villa, then posed as repairmen to supposedly fix the problem and get a look inside.

To do this, the two-man team enlisted an ISP's technical support worker, who told them the lingo to use to sound convincing, and what equipment to check.

After the visit, the FBI successfully applied for a search warrant in court and raided the villa and two others at the casino. They claim they discovered evidence that an illegal World Cup betting operation was being run from the rooms – but US magistrate Judge Peggy Leen has thrown out the evidence against Wei Seng Phua and his son.

Judge Leen ruled the phony repairmen ruse was an acceptable tactic to gain access to a suspect's property without getting a search warrant. The problem is that the FBI didn’t then tell the judge who issued the search warrant that they had done so – so the warrant was invalid.

"The court finds that the search warrant application, excised of false and misleading statements, does not support a finding of probable cause," the judge wrote in her judgment [PDF] date January 30 and published on Monday.

"Excised of errors and false or misleading statements, and supplemented with material omissions, the search warrant is fatally flawed and lacks probable cause to support the search.

"A search warrant is never validated by what its execution recovers."

Five people in the other villas have pleaded guilty to running an illegal gambling ring and were fined, expelled from the US, and banned from reentering in the country. Wei Seng (“Paul”) Phua and his son Darren Wai Kit Phua deny wrongdoing. Their case continues. ®