That position also made Kušević a member of the parliament,[1] and the highest-ranking officeholder in the realm after the Ban of Croatia as the two were jointly the head of the judiciary.

It involved 60 villages within the estate of Count Izidor Janković Daruvarski [hr] where peasants refused to pay taxes required under 1810 regulations.

[4] In 1822, Kušević and Alojzije Bužan were sent as envoys of the Zagreb County to the Congress of Verona to express gratitude to Francis I of Austria for restoring the territory south of the Sava to the kingdoms of Dalmatia, Croatia, and Slavonia.

Kušević argued that the right to determine the official language in Croatia belongs to the Croatian Parliament alone on the basis of articles of law previously confirmed by the king.

The speech led to a debate where Hungarian Diet members claimed that Croatian position is similar to that of the northern Hungarian counties (largely corresponding to the present-day Slovakia), while Croatian delegates argued that Croatia enjoyed the status of a federal realm with its own rights, laws, customs, and liberties.

Representatives of the king agreed with the Croatian position, denying the Diet the right to determine the official language in Croatia.

[7] Even though the speech was included in the record of the Diet, Kušević was displeased with the way it was abridged and had it printed and published separately as the Sermo magistri Josephi Kussevich ... protonotarii in comitiali Sessione 27. februarii 1826. pronunciatus.

In 1827, the Diet of Hungary appointed him to a commission tasked with compiling municipal ordinances and statutes and preparing proposals for reforms of public affairs.

Kušević used the information gathered to write and (anonymously) publish the first systematic work on the Croatian state right, De municipalibus iuribus et statutis regnorum Dalmatiae, Croatiae et Slavoniae in 1830.

Mati – sin – zorja (commonly referred to as the Kip domovine vu početku leta 1831) as a great patriot.