Jones was frequently styled Tyrwhitt Jones, although he adopted the latter surname only. He had inherited an estate that straddled the Welsh border. He was returned for Weymouth in 1790 on the interest of (Sir) William Pulteney, who had written to Chief Justice Kenyon on 1 Apr. 1790 offering him a seat ‘without expense’ for any friend he chose to recommend, provided he was a ‘respectable independent gentleman’.
Jones, who had joined the Whig Club on 1 May 1787 but seceded in 1792, was then out of Parliament until 1797, when he came in for Denbigh during the abeyance of the Chirk Castle interest. It was in this Parliament that Jones acquired the reputation of an independent and eccentric Member which made him a great favourite of the caricaturist Gillray. His speeches illustrate the fact that he took his own line and, thanks no doubt to the secession of the Foxite Whigs, few intervened so frequently in debate during that Parliament: yet ‘absurd’ and ‘coarse and ridiculous’ were typical reactions to his attempts at oratory.
Jones, who regarded the French revolutionary regime, the Directory in particular, as monsters of aggression, supported the address, 21 Nov. 1798, though he wished for more economy. He hailed Admiral Nelson as ‘the saviour of mankind’, 23 Nov. He supported Pitt’s income tax bill, 4 Dec., with reservations about its inquisitorial tendencies in practice, but opposed the land tax redemption bill next day as ‘the child of inordinate power’, which led to the first of many brushes with Pitt. In the later stages of the income tax bill he also turned against that, claiming that as the danger of invasion had passed it was no longer needed, 17, 19 and 27 Dec. He was one of the two Members who voted against the third reading of the bill on 31 Dec. Having reluctantly supported the use of the English militia to pacify Ireland, 12 Dec., he went on to become a keen critic of the union with Ireland, 11 Feb. 1799. He claimed that it would add 100 Members to Pitt’s ‘muzzled majority’, which provoked ‘a loud laugh’, 14 Feb. Henceforward, he became a sniper against the ‘muzzled majority’.
Jones criticized the bill to suppress seditious societies as a threat to the liberty of the press: ‘he cared not whether he should be called a Jacobin ... or exhibited in the print shops: he would do his duty’, 30 Apr. 1799. He also defended Sunday papers against their critics: ‘it was more immoral to ride on Sunday than to read a paper’, 28 May. In this he regarded himself as champion of the poorer classes; he also championed the lower paid officials on the question of salary rises in government departments, 13 June: but he emphasized the need for government economy and disapproved of the restoration of the monarchy in France as a legitimate aim of the war, 3 July. He seconded Plumer’s motion for a call of the House, 25 Sept., and Tierney’s similar motion of 22 Jan. 1800. While he did not oppose the augmentation of the militia as a means of self-defence, 30 Sept. 1799, he was opposed to the renewal of repressive measures at home, 13 Feb. 1800. On 28 Feb. he seconded Tierney’s motion against the continuance of war, claiming that the country at large was weary of it ‘and its chief advocates were now found only among contractors and placemen, whose interest it would be to continue it for ever’. It led, he claimed, to scarcity at home, 19 Mar. He could not support taxation which was designed to continue it, 17 Apr., 20 May, especially as it weighed more heavily on the landed than on the mercantile interest, 26 May.
Jones made a determined attack on the Irish union, 21 Apr. 1800, claiming that it had been achieved by corruption and would destroy the constitution: he appealed to the country gentlemen to back him, but got nowhere. He stayed away from Grey’s motion on the same subject, 25 Apr., allegedly because it did not go far enough.
Jones was much better disposed towards Addington’s administration. He explained, 24 Apr. 1801, that he disbelieved in any collusion between Addington and Pitt and had ‘almost quarrelled on the subject’ with his nearest friends. On 27 Mar. he had at last secured approval for an inquiry into the evacuation of Egypt, but his attempt to secure further information on the subject was thwarted, 1 May, and he went on to invoke ‘the bloody ghost of the brave Abercrombie’ and ‘the noble army of martyrs in Egypt’ in the hope that the former ministers would receive ‘condign punishment’, 18 May: he was again thwarted, 2 June, and having stated that he could not tell ‘who was now the minister of the country’, 27 May, attempted to persuade Addington to dissociate himself altogether from Pitt’s policy, 10 June. He congratulated Addington on achieving peace, 12 Nov. 1801, and a few days later gave notice that he would move the abolition of income tax if the minister did not do so. He soon discovered the peace to be a hollow one, 19 Jan. 1802, and was disappointed in his hopes of tax relief, 2 Feb., 12 and 17 Mar., and government economy, 10 Mar. He complained that Addington, by not distinguishing his accounts from those of the preceding ‘wasteful’ administration, appeared to condone the latter, 5 Feb.: he continued to subject Pitt to his keenest attacks, 5 Apr.
In March 1802 Jones had hoped to cut a figure as a newly made liveryman of the City when the income tax came under fire at common hall. At the meeting neither he nor his friend Robson said anything. When Addington abandoned the income tax soon afterwards, Jones was reported to be mortified, as the ‘popularity’ of bringing forward its repeal might have secured him a seat for Westminster, or London. He knew that Denbigh would be closed to him in future.
In 1802 Jones was left without a seat. In his farewell address to the electors of Denbigh he alleged: ‘I promised to serve you with fidelity, zeal and independence: I can lay my hand to my heart and say, I have done so.’ He came in for Athlone a year later on the interest of William Handcock, the very type of the Irish friends of government whom he had cordially denounced at the time of the Union. Jones himself was a different man: during the Whig secession and while possessed of an independent seat, he had been ‘disinterested and patriotic’, the symbol of ‘independence and Old England’ to the caricaturists.
Jones was obliged to look elsewhere for a seat at the election of 1806 and stood for Shrewsbury, allegedly ‘on the Paull and Burdett principles and interest’.