Topics discussed included legislative reform for prisoners, women's education, animal cruelty, trade union law and public sanitation.

At the 1875 summit, he supported fellow Japanese writer Hara Rokuro in the rolling back of the right to extraterritoriality which British citizens still enjoyed in Japan until 1899, with Baba joining the National Indian Association with Iga Yotaro on the advice of Elizabeth Adelaide Manning speaking against the issue of "The Opium Revenue of India"; afterwards visiting the social reformer Harriet Martineau.

In his spare time he took to theatre-going, watching Henry Irving in Richard III, reading the novels of Benjamin Disraeli, Bulwer Lytton and Charles Dickens.

He led an active social life in London and took to listening to preachers on Sunday such as Charles Voysey and discussing intellectual dialogue such as theism and unitarianism with William Kingdon Clifford and Kenkichi Kataoka.

In 1885 Baba was arrested on charges of possessing explosives bought from an English merchant in Yokohama together with Oishi Masami; most likely due to his exercising of free speech against the existing government; but was released after some six months.

In 1886 he went into exile in the United States, where he wrote the long essay (in English in 1888):The Political Condition of Japan, Showing the Depotism and Incompetency of the Cabinet and the Aims of the Popular Parties later dying in Philadelphia that same year.