THE RULES: FLAME

In Season 3, Sayid and Kate ascended to the upper level of the Flame with one of the Others, Beatrice Klugh, as a hostage. When they came outside the Flame station, Mikhail (Patchy), was holding Locke hostage. During this stand-off, Beatrice and Mikhail began shouting to each other in Russian.
(Lostpedia Translation from Russian)

--Beatrice: "We can't risk it, you know the rules."

--Mikhail: "There's still a way out."

--Beatrice: "We won't let them into the territory. You know what to do. It is an order."

--Beatrice: "(English) Just do it, Mikhail!"

(Mikhail takes aim at Beatrice)

--Mikhail: "(English) Forgive me"

(Mikhail then shoots Beatrice)

There are undefined Rules. Beatrice refers to "the territory" and "orders" not to allow people into a specific location. This is a possible reference to the Truce that time skipping Sawyer started with Horace and Alpert. The Hostiles did not want Dharma running around the Island, putting in new stations, having too many people running free. But it would appear that Dharma did not stop building stations outside their early territory as the Swan was being constructed in three years after Sawyer's truce. It still does not explain why Beatrice preferred death than capture or allowing a breach of the truce.