The Democratic Progressive Party was founded in September 1986, when martial law still forbade it. Opposition politicians and activists gathered in the Grand Hotel to discuss candidate selection, and the idea to form a party had come up and ended up gaining momentum.
They created an official party platform which included advocating for human rights, democracy, constitutional rule of law, liberalism, freedom of assembly, freedom of speech and a free press.
Even though their action had technically been illegal, behind closed doors they assured the Chiang administration that they will keep communism and independence a taboo, so they turned a blind eye to it, and lifted the ban on opposition parties in the same year.