Originally Posted by
indogulf
If a country's entry policy specifically states a maximum stay without visa you will have to present a valid ticket proving you will leave within the specified period. Some countries specifically state that proof of onward or return tickets is required while others do not.
Depending on the actual requirements you could be denied boarding if not holding the appropriate documents.
Partly correct. The United Kingdom, for example, does not require Americans to present evidence of return or onward travel. They do have a maximum stay requirement. But I can board a flight in New York for Heathrow without having an onward/ return ticket. It is up to the border agent to decide whether or not I will be permitted to enter, and one of the factors will be whether I have a return/ onward ticket. It is not up to DL to decide whether or not I should be allowed to fly to Heathrow on a one-way ticket.
Yes, some countries do specifically state that you must have proof of onward or return tickets, which is consistent with what I said. Proof of onward travel/ return tickets would be part of the documentation requirements, and for such countries, DL would be absolutely correct to deny me boarding without any compensation.
In the case of the OP, he/she had more than adequate documentation, and DL was wrong to deny him/her boarding. It is not up to DL to make an assessment as to whether somebody will violate the immigration laws of a country if the passenger has the proper documentation to board a flight to that country.