Thinking of packing some pot? Cramming your bag with cannabis? Stowing some CBD oil?

You could be barred from crossing the border, even if you're travelling between places where cannabis products are legal, or the products you're packing don't actually contain THC.

In light of recent lifetime entry bans granted to two Canadians, we asked an expert what border-crossers should know ahead of time.

Here are three tips from Len Saunders, a lawyer based in Blaine, Wash. who represents both travellers given the bans. Watch the full interview for more detailed answers.

1. Never have cannabis on you

"Leafy cannabis, you cannot have that on you entering the United States. That is the absolute worst thing to do, is to have leafy product on you when entering," Saunders said.

2. Don't carry cannabis byproducts

"Whether it's edibles or oils or lotions, anything related to cannabis," he said.

"CBD, THC… You cannot have those products on you when entering the United States. That will also result in a denied entry and the lifetime bar."

3. Withdraw your application if you're uncomfortable

Saunders said anyone feeling uncomfortable with questioning on current or past use, or who may have products on them, can always withdraw their application for entry into the U.S.

"They have no right to have you self-incriminate at the U.S. border," he said.

They can ask questions, but travellers can choose at any point to go back to Canada, rather than proceed into the U.S.

"It's better to have a simple denied entry than to basically put yourself in a situation where you're deemed inadmissible for life and need waivers."

With an interview from CTV News Vancouver's David Molko