The influence of his father secured him a seat in Parliament at the young age of 19: he was returned for
Westbury in the
1695 election. He brought in
a bill in the interests of
Oxford University during his first session. A Tory like his father, Bertie refused to sign the
Association of 1696 and opposed the attainder of
Sir John Fenwick. Westbury was a center of
woollen manufacture, and Bertie sponsored a bill to promote the trade. A paper he drew up in support of his brother and fellow MP
James Bertie included an attack on Lord Chancellor
Somers. It nearly provoked a dispute between the Lords and Commons, but the matter was smoothed over when Abingdon apologized to Somers and the Lords, and the paper was burned by the common hangman. He was re-elected in the
1698 election and classified by contemporaries as a Country supporter. He may have continued his support for the English textile industry. Bertie was made a
freeman and
bailiff of
Oxford in 1699. In 1700, he was identified with the interest of his half-uncle,
Thomas Osborne, 1st Duke of Leeds. He was returned uncontested in the
January 1701 election and the subsequent
November 1701 election; the retirement of his fellow MP
Richard Lewis allowed his uncle
Henry Bertie to claim the other seat at Westbury. During this year he was also appointed
recorder of
Hertford. However, the Bertie interest at Westbury was almost immediately attacked by the Whigs, perhaps taking advantage of the distressed state of the textile industry occasioned by the
War of the Spanish Succession. The London merchant
Thomas Phipps captured the loyalty of some of the officers of the borough, aided by
William Trenchard, a former MP who had triumphed over Henry Bertie on petition in 1680. Phipps and Trenchard defeated the Berties in the
1702 election, and an election petition by the Berties followed. After charges and counter-charges of bribery, the House of Commons, in a perhaps partisan judgment, declared the Berties duly elected. Bertie was made a freeman of Hertford in 1703, and was appointed counsel for the duchy of Lancaster and steward for the duchy in Oxfordshire and Berkshire. He joined the
Tackers in 1704, and unsuccessfully backed the High Tory
William Bromley for the Speakership in the
2nd Parliament of Queen Anne. In February 1708, he obtained a leave of absence from Parliament, and declined to stand for Westbury in the
1708 election, perhaps due to family affairs. ==Marriage and death==