He was born on 24 May 1839. He was educated in Konstantinova military school. After graduating the school he was called to the 7th degree of the official rank of the civil servant – court counsellor. The abolition of serfdom (a manifesto signed by Alexander II of Russia in 1861) and the avoidance of conflict situations with peasants and landlords furthered the establishment of the institute of peace intermediates.
On 29 January 1864 P.Dubrovin was appointed to the post of the chairman of the first peace intermediate centre in Dinaburg. Occupying this post he got his first awards – the Order of St.Anna of the 3rd class for flawless service, and the Decoration – for the bringing the emancipation manifesto into effect. In 1864 P.Dubrovin was awarded medal “For Scotching of the Polish Mutiny 1863-1864”. In 1874 P.Dubrovin became the director of the first public bank in Dinaburg, but in 1876 he was elected as mayor of the city for the first time and filled this post till his death.
P.Dubrovin made huge contribution in the development of the city. He was initiator of the establishment of the voluntary fire-fighters association, secured the establishment of women’s progymnasium, and later – its transformation into the gymnasium. Later women’s gymnasium became the biggest educational institution in the city. With the active participation of P.Dubrovin there was established “Relief Association for the Deprived Students of Women’s Gymnasium”, but in 1879 – “Mutual Credit Association”, where he was committee chairman. Later was opened a state bank office, on Big marketplace there was built a trade centre with its own traditions – each year at the end of winter, on Maslenitsa (aka Pancake week), was organized sledding. Dubrovin died on 23 May 1890 and was buried in Orthodox cemetery.
In the end of 19th century there was established a park that had an entrance arc and a stage for concerts. The park has remained till nowadays and it has Dubrovin’s name. There is a monument to Dubrovin in this park.