What are your rights and obligations at border control?
Fewer rights than you would have almost anywhere else, and more obligations — because the border is a space where ordinary protections are reduced by design, and this catches travellers out routinely.
What officers can generally do:
Refuse entry to non-citizens, without the process you would expect elsewhere. A visa is permission to travel and request entry, not a guarantee of admission — the decision is made at the border.
Question you about your purpose, funds, accommodation and intentions, and require answers.
Search your baggage, generally without needing individual suspicion.
Examine electronic devices, which is the power most travellers do not anticipate. Practice varies: in some countries officers may require you to unlock a device or provide a password, and refusal can mean denial of entry for a visitor, or detention and device seizure.
Take biometrics, and check databases.
Detain you for further examination.
What citizens retain. A citizen generally cannot be refused entry to their own country — the strongest right there is. Other powers, including device examination, may still apply.
What is expected of you:
Answer honestly. Deception at the border is a serious matter and can produce long-term bans that follow you across systems.
Carry evidence of your purpose — return ticket, accommodation, funds, invitation, employer letter — and be able to explain your trip clearly.
Comply with declaration requirements, including cash above thresholds, restricted goods, food and plant material.
What actually causes problems:
Vague or inconsistent answers, particularly about how long you will stay and how you will support yourself.
Evidence of intending to work or live, where you hold a visitor status.
Frequent repeated visits, which read as residence.
Previous refusals, which are recorded and must generally be disclosed on later applications.
If refused: you are generally returned at the carrier's cost, may be detained meanwhile, and should ask for the reasons in writing. Appeal rights for visitors are limited, and legal advice is worth taking before reapplying.
General information, not legal advice.