Weeknotes 74 - To review and regret

The right to go where you want is an important human freedom in itself. It is precisely this freedom, and all that this freedom makes possible, that is taken away by imprisonment. Freedom of movement is also a prerequisite to many other freedoms. If people are to be free to live their lives as they choose, so long as this does not interfere with the legitimate claims of others, they have to be free to move where they want. Thus freedom of movement contributes to individual autonomy both directly and indirectly. Open borders would enhance this freedom.

Of course, freedom of movement cannot be an unqualified right, if only for reasons like traffic control and other requirements of public order, But restrictions require a moral justification, i.e., some argument as to why the restriction is in the interest of, and fair to, all those who are subject to it. Since state control over immigration restricts human freedom of movement, it requires a justification. This justification must take into account the interests of those excluded as well as the interests of those already inside. It must make the case that the restrictions on immigration are fair to all human beings. There are restrictions on border crossing that meet this standard of justification (e.g. limiting the entry of terrorists and invading armies), but granting states a right to exercise discretionary control over immigration does not.

— Joseph Carens, from The case for open borders, the article summarising the conclusion of The Ethics of Immigration