In 1664 he was elected, as member for Port Royal, to the first house of assembly; he was sent to prison by the speaker for contempt of his authority, was brought before the governor and council, reprimanded and released.
Using Assistance he brought in French pirate Du Mangle and English turncoat buccaneer Francis Witherborn.
[1] The following year he sailed to Cuba and Hispaniola 'to look after pirates and privateers' (including Captain Yellows)[2] and to Havana 'to fetch away the prisoners.'
In 1677 and the two following years 'Lieutenant-Colonel Beeston,' as speaker of the house of assembly, zealously promoted the opposition to the efforts of the governor, the Earl of Carbery, to assimilate the government of Jamaica to that then existing in Ireland, and to obtain an act settling a perpetual revenue upon the crown.
He found it still suffering from the effects of the fearful earthquake of 7 June 1692, followed by an epidemic fever, and in October Beeston writes to Lord ––: 'By the mortality which yet continues I have lost all my family but my wife and one child, and have not one servant left to attend me but my cook, so it is very uneasy being here.'
[3] In 1699 Beeston, at the instigation of the home government, helped to complete the ruin of the Scotch colony at Darien by a proclamation forbidding the inhabitants of Jamaica to trade with them or afford them any assistance.
Yet for some time he contrived to secure for himself a greater share of popularity than had been the lot of any of his immediate predecessors, and he dissolved the assembly of 1700 in tolerable harmony with all its members.
Selwyn died before it could be presented, but it was received by the new governor, Colonel Beckford, grandfather of the lord mayor of London, who said that he did not consider Beeston responsible to the house of assembly, but to the king.