The base for the establishment of the Seimas Ombudsmen’s Office (hereafter referred to as SOO) of the Republic of Lithuania is Art. 73 of the Constitution of the Republic of Lithuania. The model of the SOO has been taken from the Swedish Parliamentary Ombudsmen. Initially, there were five Seimas Ombudsmen. In 2010 this number was reduced to two Seimas Ombudsmen.

The commitment of the Seimas to ensure human rights to all is the other mechanism that gives SOO its legitimacy. SOO is the only state institution in Lithuania responsible for human rights issues in general (Equality Ombudsman and Children Rights Ombudsman have their jurisdictions in the fields of equality and non-discrimination and children rights).

SOO mandate has shifted from the classical Ombudsman institution investigating complaints to the one of a human rights agency addressing all human rights issues. Performing its function of investigation of complaints, the SOO is limited to the right of good public administration. However, in practice, this right is interpreted as covering all fundamental rights.

However, the Seimas Ombudsmen does not investigate the activities of the judicial branch of state power. The Seimas Ombudsmen can investigate the possible violation of the right to good public administration in the courts. The function for a promotion of human rights has no limitations, and the Human Rights Division is responsible for promoting human rights.

The mandate of the SOO is exercised by investigation of complaints, by regular inspections carry out NPM function, by meetings with different stakeholders and using other appropriate methods for the promotion and protection of human rights. The jurisdiction of the SOO covers the whole territory of the Republic of Lithuania.