Arden, according to his obituary in the Gentleman’s Magazine (1804, p. 384), after being called to the bar ‘fixed his residence in Lincoln’s Inn ... and it is said he there lived on the same staircase’ with Pitt, ‘and they used to associate very much together’. Through Pitt’s influence he was made solicitor-general and shortly afterwards brought into Parliament, and when Pitt resigned Arden followed him. ‘There is great dissatisfaction in the House of Commons’, he wrote to Lloyd Kenyon on 8 Apr. 1783, ‘but what it will end in, no one can tell. For my part, I am heartily sick of politics, and should be very glad never to set my foot in the House of Commons again.’ And on 14 Apr.
He attacked Fox’s East India bill, wrote Wraxall (iii. 180), ‘through every stage with great pertinacity and spirit, not unaccompanied with legal ability’; it was, he told the House on 8 Dec. 1783, ‘a private job’.
He was one of Pitt’s chief lieutenants on the Treasury bench, and his interventions in debate extended to subjects outside his judicial offices. On 18 Apr. 1785 he ‘very ably’ supported Pitt on parliamentary reform.
‘Arden’s merit’, wrote Wraxall (iv. 151-2), ‘seemed to consist principally in the strong predilection manifested towards him’ by Pitt; without this ‘never would Arden have reached the heights of the law’.
He died 19 Mar. 1804.