[opendoor]

Originally Posted by New Era

So when my wife attempted to become a Canadian citizen, and was told by the US consulate that she could not do so without renouncing her American citizenship, the consulate gave her wrong information?

Unless there were extenuating circumstances that'd make her ineligible, then yes. While the law states that the act of obtaining naturalization in a foreign state is an expatriating act that would cause a loss of citizenship, the courts and the government have made it quite clear how this is to be interpreted. In order for that to happen the act has to be done with the intention of relinqueshing that person's US nationality. And the State Department explicitly states various scenarios that do not meet that standard:

As already noted, the actions listed above will result in the loss of U.S. nationality if performed voluntarily and with the intention of relinquishing U.S. nationality. The Department has a uniform administrative standard of evidence based on the premise that U.S. nationals intend to retain United States nationality when they obtain naturalization in a foreign state, declare their allegiance to a foreign state, serve in the armed forces of a foreign state not engaged in hostilities with the United States, or accept non-policy level employment with a foreign government.

In light of the administrative premise discussed above, a person who:

1. is naturalized in a foreign country;
2. takes a routine oath of allegiance to a foreign state;
3. serves in the armed forces of a foreign state not engaged in hostilities with the United States, or
4. accepts non-policy level employment with a foreign government,

and in so doing wishes to retain U.S. nationality need not submit prior to the commission of a potentially expatriating act a statement or evidence of his or her intent to retain U.S. nationality since such an intent will be presumed.

https://travel.state.gov/content/tra...tionality.html

So in those examples, it is presumed by the US government that the US citizen intends to retain their US nationality and thus they do not lose their citizenship nor do they need to provide evidence that it was not an expatriating act.

All that said, there are certainly rigorous requirements to obtain Canadian citizenship by marriage, including having to become a permanent resident and meet the residency requirements for Canada.