the resistance by the Baltic people to the Soviet regime, and the uninterrupted functioning of rudimentary state organs in exile support the legal position that sovereign title never passed to the Soviet Union, which implied that occupation sui generis (Annexionsbesetzung or "annexation occupation") lasted until re-independence in 1991.
They have also argued that in accordance to the internal Soviet laws and constitution, restoration of independence was illegal and the Baltic republics could only become newly created sovereign entities via the secession laws of the USSR.
The document stated a number of principles such as freedom of expression, religion, assembly and association.
These principles were further elaborated in the Provisional Constitution of 1919 and the first Constitution of 1920.
On one hand, legal recognition of Baltic incorporation on the part of other sovereign nations outside the Soviet bloc was largely withheld based on the fundamental legal principle of ex injuria jus non oritur, since the annexation of the Baltic states was held to be illegal.
The four countries on the Baltic Sea that were formerly parts of the Russian Empire – Finland, Estonia, Latvia and Lithuania – consolidated their borders and independence after the Estonian, Latvian and Lithuanian independence wars following the end of World War I by 1920 (see Treaty of Tartu, Latvian-Soviet Riga Peace Treaty and Soviet-Lithuanian Treaty of 1920).
while under Soviet rule and German occupation from 1940 to 1991.The prevailing opinion accepts the Baltic thesis of illegal occupation and the actions of the USSR are regarded as contrary to international law in general and to the bilateral treaties between the USSR and the Baltic states in particular.