He was the owner of a whaling business based in Westminster, London and held a seat in the House of Commons from 1852 to 1853, and from 1857 to 1867. Miller lived at 1 Millbank, London and was a "ship-owner and sperm-oil refiner and merchant". He ran a "Sperm Oil merchants and Spermaceti refiners" business called "Messr T J Miller & Son" from Dorset Wharf, on the site of the current Victoria Tower Gardens by the Houses of Parliament and exhibited at the Great Exhibition of 1851.
Miller was elected as Member of Parliament for Maldon in the 1852 general election.
However an election petition and an investigation into corrupt practices in the borough (in which he was not implicated) led to the election being declared void on 18 March 1853. The writ was suspended and the by-election was not held until August 1854.
In 1831 he appeared as primary prosecution witness at the trial of a 19-year-old George Fox at the Old Bailey where Fox was convicted for pickpocketing Miller"s silk handkerchief and was sentenced to be transported for fourteen years.