The U.S. Customs and Border Protection agency says a Canadian man shouldn't credit his iPad for helping him enter their country.

The agency responded Wednesday to the case of Martin Reisch — a Montrealer who says he used a scanned copy of his passport and a regular driver's licence to cross into the U.S.

Reisch's border experience offers a glimpse into how U.S. Customs officers process Canadians who fail to present a document listed under stricter travel requirements now enforced at the 49th parallel — such as a passport.

A spokeswoman for U.S. Customs said scanned or digital images of passports are not accepted by border guards.

"The assertion that a traveller was admitted into the U.S. using solely a scanned image of his passport on an iPad is categorically false," Jenny Burke said in a statement.

"In this case, the individual had both a driver's licence and birth certificate, which the CBP [U.S. Customs] officer used to determine identity and citizenship in order to admit the traveller into the country."

Reisch, however, has said he only handed the officer his iPad and driver's licence — and nothing else. He said he had forgotten his hard-copy passport at home.

The Montrealer was about a 30-minute drive from the Vermont border last Friday when he realized he had left his passport at home — a two-hour journey away.

He quickly remembered that a digital image of the document was stored on his iPad and decided to try his luck at the U.S. border anyway.

Reisch said the customs agent took his computer tablet and driver's licence into the checkpoint office for about five minutes before allowing him to continue into the U.S.

Burke said customs officers will not determine identification from a scanned or digital copy of any document compliant under a program that has imposed tougher entrance requirements on Canadians since 2009.

The Western Hemisphere Travel Initiative was introduced in the wake of the Sept. 11, 2001, attacks in the U.S. Under the program, the required documents include a passport, an enhanced driver's licence or a trusted traveller card, such as the Nexus pass.

The U.S. Customs website states that Canadian citizens travelling to the U.S. by land or sea are "required" to present one of the approved documents.

But, as Reisch's case revealed, there is some elasticity in whether someone can still pass through.

Burke said a Canadian traveller can cross the border, by land or sea, without presenting one of those approved documents.

There are no guarantees, however, that the individual will get in.

"If a traveller does not present WHTI-compliant documents, CBP officers must determine identity and citizenship using a variety of other means, or deny entry," Burke said.

A U.S. official, who spoke on condition of anonymity, said the ultimate decision whether to allow a Canadian to cross the border is left up to the discretion of the officer on duty.

"We've been flexible in the implementation of the law, but the law is very clear and establishes that they need to have an approved travel document when they're coming to the U.S.," the official said.

"Any other document is not an approved travel document, and if they don't have [one], they may be denied entry or they may face a delay as the officers will have to confirm their identity and citizenship."

The official said people entering from the Canadian border have had a compliance rate of about 98 per cent since the tighter rules were introduced.

"It's very rare to encounter travellers who do not have an approved travel document," the official said.

An evaluation report released last summer by the Canada Border Services Agency found that millions of Canadians acquired passports and other secure identification documents in recent years to ensure they can still travel to the U.S.

The report revealed that around 60 per cent of Canadians had a passport in 2009-2010, up from 36 per cent four years earlier, before the U.S. security initiative began.

It also found that another 125,000 people in Quebec, Ontario, Manitoba and British Columbia had obtained enhanced driver's licences with secure features that allow entry to the U.S. by land or sea.

Previously, Canadians could be admitted to the U.S. with a simple verbal declaration of citizenship or by presenting a commonly held document such as a driver's licence or birth certificate.