The border patrol can certainly be sued but whether you have a valid case is an issue that is beyond the scope of this forum and should be discussed in detail with a local attorney that handles these cases routinely. I'm not certain that being retained in handcuffs is considered unlawful detainment - it could be considered a valid tool to insure the safety of the officers.
Nevertheless, you would be well served to discuss this this matter with a local civil rights attorney.
On these facts, without more, this incident is not likely to be sufficient for a suit and unlikely to be accepted as a contingency matter by an attorney. Even if you could sue and prevail, your damages would not cover your costs for brining the suit.
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