TORONTO -- The Canada Border Services Agency (CBSA) was not justified in revoking a Nexus travel card simply because its holder tried to leave the country with undeclared cash, a judge has ruled.

Canada's border authority says it will not appeal the April 29 ruling and will consider the judge's words as it moves forward with the Nexus program, which allows members travelling between Canada and the U.S. to speed their travels by bypassing lineups of non-Nexus members.

"The Canada Border Services Agency is reviewing the ruling and will take it into consideration in the regular assessment of the program," a spokesperson for the CBSA told CTVNews.ca in an email on Wednesday.

The case in question centred around a Montreal businessman whose Nexus membership was cancelled in 2019, after he was caught attempting to fly to China with the equivalent of a little more than $12,000 in cash. Travellers departing the country are required to declare if they have more than $10,000 in cash with them; this man had not done so.

The man appealed this decision, as a result of which the CBSA lowered the amount of time until he could reapply for Nexus membership from six years to two – but upheld the original decision to strip him of it.

It was this upholding that Federal Court Justice John Norris overruled, stating that he found it to be "lacking in transparency, intelligibility and justification."

Norris' decision focused on the CBSA requirement that Nexus cardholders be "of good character," a term that is not specifically defined in legislation. In upholding the revocation of this traveller's membership, the CBSA said that it included "factors such as whether there has been an infraction of the laws of Canada and the U.S. and, in particular, the laws administered by the CBSA, which undermines the confidence of the CBSA that the applicant will comply with all the program requirements."

The judge found that the CBSA had not provided adequate evidence as to why they found that the man would not meet this threshold.

"There is no explanation for why this caused the decision maker to lose confidence that the [traveller] would comply with all the requirements of the Nexus program in the future," Norris wrote in his decision.

"Perhaps if the applicant had intentionally failed to disclose the funds or had attempted to conceal the funds or if the funds were linked to money laundering or terrorist financing, no further explanation for why he was not trustworthy would be required. But this is not what the decision maker found."

In fact, Norris said, the CBSA seemed to agree with the businessman's position that carrying the extra money without declaring it was an "honest mistake." He had been found at Trudeau International Airport in Montreal with the equivalent of just over $10,000 in U.S. dollars, as well as an envelope in a pocket of his luggage that contained the equivalent of $2,100 in euros.

The businessman said that the envelope had been left in his luggage from a previous trip, without his realizing it. There is no suggestion that the CBSA disputed this claim. He was fined $250, the lowest amount allowed for this offence, and allowed to carry on his way.

Norris wrote in his decision that it was not clear how the CBSA could reach a determination that those events qualified as proof the man is not "of good character" based on the evidence that was provided.

"While past behaviour can be a reliable predictor of future behaviour, this is not always the case. People can and will change their behaviour in response to any number of different factors," he wrote.

"In the present case, after everything that has happened as a result of the mistake he made on October 28, 2019, one might expect the applicant to be much more careful in the future."

Had the CBSA offered "at least some explanation of how [it] linked the [traveller]'s past behaviour to his future behaviour through the assessment of his character," the judge wrote, the final decision could have been different.

The court decision does not mean that the businessman's Nexus membership will be reinstated. Norris ordered only that the case can go ahead, with another judge ruling on the fate of the man's Nexus status.