Cooke, the son of a distinguished barrister, practised at the bar at least until he succeeded to the family estate. The office of chief prothonotary, which he held for life, had also been held by his father and grandfather.
In 1754 he was returned unopposed for Middlesex, and under George II was a Tory—Horace Walpole called him ‘a pompous Jacobite’.
On 11 Dec. 1761 Cooke moved for papers on relations with Spain—‘in a plain and decent manner’ wrote Harris; and on 9 Dec. 1762 voted against the peace preliminaries. On 22 Feb. 1763 he supported Sir John Philipps’s motion for a committee on public accounts. He voted with Opposition on Wilkes, and was carried to the House ill of the gout to attend the great debate on general warrants, 17-18 Feb. 1764.
When the Rockingham Administration met Parliament in December 1765 Cooke was asked to second the Address. Newcastle told him that Administration wished ‘to have the sanction of an independent man at their setting out’
I look up to you for the rule and conduct of my political life. Were you at the head of affairs the pride of my heart would be to be known and distinguished as your devoted friend. As the ministry are now composed I do not wish to take any part that has the appearance of connexion, where you are not connected.
Pitt disclaimed any tie with Administration, and Cooke declined Newcastle’s request.
In the debate of 17 Dec. 1765 he ‘treated the whole American affair as a mere mob’;
No speeches by Cooke are recorded during the last two years of his life. He voted against Administration on the land tax, 27 Feb. 1767, and apologized to Chatham for his vote:
My particular situation as Member for Middlesex, and being chose by the unanimous and affectionate voice of my constituents, rendered it impossible for me not to vote for the three shillings, as I am certain had I done otherwise I should at once have forfeited their good opinion ... Under these circumstances I hope your Lordship will not take it amiss.
On nullum tempus, 17 Feb. 1768, he voted with Administration.
His interest in Middlesex was strong enough to ensure his return in the contested election of 1768, although he was ill in bed with gout on election day.
