Ellen Richardson says she was turned away by a U.S. customs agent at Pearson International Airport on Monday because she had been hospitalized for clinical depression in June 2012.
She missed her flight to New York City and a Caribbean cruise, for which she had paid $6,000, as a result.
"I was in shock. I was completely in shock," Richardson said Friday on CBC's Metro Morning. "I had no idea how that was relevant to my seeking entry into the U.S. for a holiday."
Only later, she added, did she wonder how the agent knew her history in the first place.
"It really hit me later — that it's quite stunning they have that information."
Though U.S. officials have access to police records, medical records are supposed to be held in the strictest confidence.
Richardson's stay in hospital was preceded by a 911 call, placed by her mother, but she says police were never involved, just an ambulance.
U.S. border guards are allowed to bar anyone they deem a threat to themselves, others or their property.
Richardson says she has been on several cruises since 2001, all of which required U.S. flights, with no problems.
She has hired a lawyer and turned to her member of Parliament for answers.
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