Many of our readers may be pleased about the soon-to-be legalization of marijuana. These same readers may find themselves feeling slightly relieved, as gone are the days where smoking pot also meant breaking the law. Right? Wrong.

Although cannabis is about to become legal in Canada, there are still many important legalities that must be borne in mind, or else you could find yourself in some hot water.

One of the biggest concerns immigration lawyers have, with regards to the legalization of marijuana, are the implications at the United States border. If a person admits to smoking marijuana, presently or in years past, or if a person admits to having ties to U.S.-based cannabis companies, they could be in serious trouble at the border and could find themselves banned from entering the U.S. – indefinitely.

This is because the recreational use of marijuana is not yet legal federally across the United States. Unlike in Canada, criminal law in the U.S. is regulated state by state. In plain terms, what this means is that the consequences for committing a crime in the U.S. vary state by state, whereas in Canada, we are all subject to the same Criminal Code. When marijuana becomes legal in Canada, it's legal everywhere in Canada, but in the U.S., only nine American states have legalized cannabis for recreational purposes. It is currently illegal under U.S. Federal Law. So while us Canadians may be free to use cannabis as we please, there's a line to be drawn, and that line is at the U.S. border (which operates under U.S. Federal Law).

According to the Canadian Border Services Agency, both the U.S. Customs and Border Patrol and the Canadian agency allow access to their respective countries based on the "circumstances" of each traveller. Unfortunately, some circumstances matter more than others to U.S. border agents. One such circumstance they aren't a fan of includes those that link travellers to marijuana, whether through consumption or their employment. According to U.S. Customs and Border Patrol, if an individual works in the Canadian cannabis industry, he or she may be turned away from the border or banned from entering. As a case in point, a businessman from Vancouver was recently banned for life from the U.S. as a result of his investments in U.S. marijuana companies.

Immigration lawyers across Canada have spoken out about the dozens of cases they have recently encountered where Canadians have been denied entry to the U.S. as a result of their connections to the cannabis industry. Some of these attorneys have gone so far as to advise their clients, who work with American marijuana companies, to not cross the border. If they do, they may be "aiding and abetting the U.S. marijuana industry," which still is illegal.

However, it is not just those who work or invest in the cannabis industry who may have difficulties in crossing the border. The federal prohibition of marijuana in the U.S. will continue to be a serious cause for concern for a lot of Canadians. For example, anyone who does so much as admit they have used cannabis may similarly be banned from the U.S. for life. The most famous example of this happening is with Ross Rebagliati, a Canadian Olympic snowboarder. Rebagliati was banned from the U.S. for simply admitting that he had used marijuana in the past.

Not surprisingly, a denial of entry could have serious ramifications for those who are travelling to the U.S. for business or to be reunited with their families. In one case in particular, three individuals from Vancouver who were looking to sell agricultural equipment to a cannabis business in Washington State (where cannabis happens to be legal) were banned from the U.S. for life, and of course, they didn't make the sale.

Once the recreational use of marijuana becomes legal, it should come as no surprise that more and more Canadians will likely begin to consume the once illegal substance. And with more consumers comes more concern. The more people using marijuana in Canada means there is a greater possibility that more people would be barred from entering the U.S., either temporarily or permanently.

In an effort to avoid such consequences, many Canadians may be tempted to lie to U.S. Border Officers, or refuse to answer their questions. Refusing to answer could result in you being barred from entering that one time, but it likely would not lead to a permanent ban, as can be the case with admitting to smoking marijuana previously. As for lying to Border Officers, this can result in a 5-year ban for misrepresentation, or worse, a forever ban. Given that officers can search the internet or a person’s electronic devices to ascertain that individual's activities—including where that person works or what organization they are associated with—many will be caught if they are not forthcoming.

As immigration lawyers advise, a determination of inadmissibility will not be easy to overcome. Canadians who do find themselves banned can apply for a temporary waiver to allow entry, but the process can take up to a year, and the waiver must be renewed every so often.

Due to the jurisdictional issues, there is unfortunately very little the Canadian government can do in order to prevent U.S. Customs and Border Patrol from asking travelling Canadians about their marijuana use.

At the end of the day, whether your ties to marijuana are work-related, investment related, or recreationally related, you should be wary about crossing the border.