Ribbed by his fellow Catholic campaigner Lord Acton, the Cambridge historian, as ‘Pegg-Wosser’, Wegg-Prosser’s growing sympathies with Rome curtailed his parliamentary career.
It seems likely that Haggitt, whose father was a clergyman, picked up his High Church beliefs from his time at Oxford, where he graduated with a first in mathematics, whilst the ‘Oxford Movement’ or Tractarianism was at its peak. He came forward as a candidate for Herefordshire at the 1847 general election, declaring support for the church and state, and promising to give free trade a ‘fair trial’.
In his first session, Haggitt cast votes against Jewish relief and Joseph Hume’s ‘Little Charter’ of political reforms. He divided with the Peelites in favour of the income tax resolutions and for the repeal of the navigation laws, 13 Mar., 9 June 1848. On the other hand, he joined the Derbyites in casting the first of three votes in favour of Disraeli’s motions for agricultural relief in 1849.
In 1849 he spoke twice and on both occasions his High Churchmanship was evident. He thought that the strongest objection to the proposed legalisation of marriage to a deceased wife’s sister was that it would place the church and state at odds, and thereby weaken the establishment, 3 May 1849. The fundamental religious objections to the measure trumped any social grounds put forward by its advocates. Furthermore, the issue was part of a broader battle between the spirit of obedience to God’s laws and the spirit of ‘laxity and licentiousness’.
In unsuccessfully moving the rejection of the clergy relief bill, 25 July 1849, Haggitt pointed to the lateness of the session, but also complained that the state was meddling in ecclesiastical affairs. In July 1849, after succeeding to the very substantial estates of his great uncle, Rev. Dr. Richard Prosser, prebendary of Durham, including a personal estate estimated at over £250,000 by the Oxford Dictionary of National Biography, Haggitt assumed the name Wegg-Prosser.
His opposition to Berkeley’s motion to reconsider the corn laws, 14 May 1850, gave the clearest indication of his Peelite allegiance, and he divided with both Conservative factions against the Whig government’s foreign policy, 28 June 1850. His support for the reduction of malt duty, 6 July 1850, was a sign that, with the exception of restoring agricultural protection, he generally sympathised with measures to relieve farmers.
In the 1851 session Wegg-Prosser divided with the Peelites in all the key votes on financial policy, aside from Disraeli’s motion on agricultural distress, 13 Feb. 1851, which he supported. He opposed Herries’ amendment to the budget resolutions, Hume’s amendment on income tax and Disraeli’s financial resolutions, 7 Apr., 2 May, 30 June 1851. In the same year, he made two brief, but polished, speeches in defence of religious liberty. On both occasions he provided an elegant consideration of both sides of the argument. Expressing his support for the alteration of the parliamentary oath to allow Jews to sit in the House of Commons, 3 Apr. 1851, he noted that Britain was not ‘exclusively Christian’, so it was bogus to argue, as Ultra-Protestant MPs did, that Parliament must remain a Christian assembly. He also rejected as ‘utterly worthless’ the view that Jews (like Roman Catholics) had a divided allegiance. In Wegg-Prosser’s opinion ‘every one born in this country, and making it his own, had a right to the privileges of British subjects’. In conclusion, he ‘could see no reason why persons professing the Jewish or any other religion whatever, should be excluded’. This was not only a notably progressive viewpoint at this time, but also revealed how Wegg-Prosser’s concept of religious liberty had developed since he voted against Jewish relief in 1848.
Having welcomed Russell’s efforts on behalf of Jewish emancipation, Wegg-Prosser was bemused at the prime minister’s ecclesiastical titles assumption bill, produced in response to the Pope’s establishment of a Catholic hierarchy in England in 1850. Explaining his opposition to the bill, 15 May 1851, he expressed a low opinion of the quality of the debate. Too much of the discussion had been characterised by attacks on the Catholic religion or the shortcomings of the political systems of Catholic countries rather than the points at issue. The so-called ‘papal aggression’ had not threatened the ‘social harmony’ of England, nor would it increase the political power of the Pope, undermine English law, or diminish the royal prerogative, as anti-Catholics claimed. There was much ‘national vanity’ in the claim that Britain’s honour had been insulted by the Pope’s actions. Above all, Wegg-Prosser dismissed the argument that the popular clamour in the country meant that Parliament had to be seen to ‘do’ something. On the contrary, he argued, ‘the duty and functions of the House of Commons was to reflect, not the wild outcry of mobs, but the calm and deliberate opinion of the community’.
After casting votes against electoral and franchise reform, Wegg-Prosser’s last significant intervention was again in a religious debate. When criticising the Regium Donum (a state grant to Protestant Dissenting ministers in Ireland), he argued that the state assumed a ‘semi-infidel character when it began to support simultaneously half a dozen religions’, 10 June 1852. However, he admitted that it was wrong to withdraw such endowments unless on ‘some clear, large and statesmanlike principle’ and as part of a general scheme.
From September 1851 Wegg-Prosser had been in regular correspondence with John Henry Newman, the leading Catholic convert.
Wegg-Prosser devoted much of his later life to promoting the Catholic revival. In 1859 he founded a Benedictine monastery at Belmont, his seat, which evolved into Belmont Abbey.