WASHINGTON (CNN) -- For U.S. and Canadian citizens, the jig is up.
Beginning January 31, citizens of both countries must present proof of citizenship and a government-issued ID when entering the United States at land border crossings and sea ports.
Currently, U.S. citizens can enter the United States simply by making an "oral declaration" -- that is, saying they are citizens and convincing the border officials that they are. No written documentation is required at land or sea ports. Citizens don't need a passport, a driver's license, or even a receipt from their local power company or dry cleaners.
The same is true for residents of Canada and Bermuda seeking entry into the United States.
But as the government continues to tighten border security, the centuries-old practice of accepting oral declarations is coming to an end, and even tighter requirements are on the way. Beginning in June 2009, travelers will need a passport or some other form of government-approved border ID cards, which are now being developed.
The January 31 change is the easy step, many say, largely because of the mistaken perception people have that proof of citizenship is already required.
"Most people believe they already need a driver's license or some form of identification," said Sarah Hubbard of the Detroit Regional Chamber in Detroit, Michigan. "They can't fathom the fact that right now, you don't need anything."
Frequent border crossers claim some border agents foster that misperception, telling them government-issued IDs are mandatory. (Passports are already required for air travel.)
In a nutshell, here are the changes as of January 31:
Interestingly, despite the stern language in government pronouncements, the January 31 change will not entirely stop border crossers without credentials.
"At the end of the day, my understanding is the U.S. Constitution is always going to allow a U.S. citizen to come into the U.S.," Hubbard said, and federal officials acknowledged.
There will always be instances when people arrive at the border without identification, officials say. But border officials say travelers will be swayed to provide documentation by the convenience that appropriate IDs bring. Travelers will also be swayed by the inconveniences they'll face when they don't have appropriate identification.
While some expect the January 31 change to be relatively uneventful, others are predicting doom.
"If DHS goes through with this, we'll have backups lasting five or six hours in places like Buffalo, Detroit and Seattle," New York Sen. Charles Schumer said, according to the Albany Business Review. Schumer said that recent congressional action to postpone the passport requirement also should have postponed the end to "oral declarations."
Exactly how many border crossers already carry proof of identity and citizenship is unknown, but is believed to be high, Customs and Border Protection spokeswoman Kelly Klundt said.
"The intention is to raise awareness that document requirements are changing, to get people accustomed to carrying documents," Klundt said. And the documents they are required to carry are the same documents needed to apply for passports, enhanced driver's licenses, or other credentials that will eventually meet congressional mandates for crossing the border.
The incremental changes at the border, and repeated delays, have confused the public, said Gordon Orr of the Windsor, Essex County & Pelee Island Convention & Visitors Bureau in Ontario. "Even us in the tourism world are confused because it keeps changing," he said.
His group has created a Web site to tell potential visitors what they need to cross the border.
"It's sad to think that people out there now are not coming to Canada because they don't think they can get back without a passport," he said.
So what will happen January 31?
"The real issue is how it is implemented," said Perrin Beatty, president of the Canadian Chamber of Commerce. "The real issue is to what extent is there discretion."
If officials take a strict approach, Beatty expects there will be traffic jams at the border rivaling last year's "Summer from Hell," during which Canadian authorities had to set up portable outhouses to accommodate people stuck in bridge traffic.
U.S. officials tell him "they will attempt to implement it in a sensitive way," he said. "I hope that is so."
Klundt said she believes the public will be quick to adapt to the changes, likening it to efforts to promote seat belt usage.
"You know what, everybody wears their seat belt now, it's no big deal," she said. "I kind of feel like this is one of those situations." E-mail to a friend
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