The Federation's Rigel Demilitarized Zone Commission was formed on reference stardate 1/9709.01, towards the end of the Four Years War between the Federation and the Klingon Empire, to decide the fate of Orion refugees and officially determine the borders of the Orion Neutrality Area after the war's conclusion. They met on Starbase 27 and were led by Commissioner Dzwonkowski.
On stardate 1/9806.29, the Commission visited the Orion homeworld of Botchok (Rigel VIII) and met with the Botchok Planetary Congress (BPC) in a closed session, where Dzwonkowski outlined their plan. (FASA RPG - The Orions module: Book of Common Knowledge)
The BPC members were outraged by the plan, and rioting broke out in the Congress, leaving two of them dead. But under protest and with a narrow majority, the BPC capitulated. By unilateral treaty, Orion space legally became the Orion Neutrality Area. (FASA RPG - The Orions module: Book of Deep Knowledge)
Shortly afterwards, Dzwonkowski and BPC President Vloun signed the Orion Emigration Act, on stardate 1/9808.15. This required the registration of all Orions in Federation space. (FASA RPG - The Orions module: Book of Common Knowledge)