Lawless, Valentine Browne (1773–1853), 2nd Baron Cloncurry , radical, was born 19 August 1773 at Merrion Square, Dublin, the only surviving son of Nicholas Lawless (1733–99), woollen merchant, brewer, and banker, who became 1st Baron Cloncurry in 1789, and Margaret Lawless (née Browne). Educated privately at Portarlington, Queen's Co., and at Blackrock, Co. Dublin, he entered TCD in 1789, graduating BA (1792). After completing a tour of Europe (1792–5) he returned to Ireland, where he joined the United Irishmen and the loyalist yeomanry. Pressurised by his father, he decided to study law, and was at Middle Temple 1795–8. He later claimed that at a dinner party in spring 1797 he heard the prime minister, William Pitt, discuss his plans for a legislative union with Ireland, prompting him to write an anti-union pamphlet in response. Like many of the claims in his published recollections, the story is unreliable. During 1797 he helped Arthur O'Connor (qv) form his United Irishman newspaper The Press, and Leonard MacNally (qv) informed Dublin Castle that Lawless was its principal shareholder. In October 1797 Lawless attended a meeting of the executive directory of the United Irishmen, of which he was elected a member; throughout this period and after his return to London he was carefully watched by the British secret service. His friendship with O'Connor, and the fact that he provided funds for Fr James Coigly (qv), aroused deep suspicion. After the outbreak of open rebellion in Ireland he was arrested at his lodgings in Pall Mall on 31 May 1798 on suspicion of high treason, and imprisoned for six weeks in the tower of London. Arabella Jefferyes (qv), sister of the earl of Clare (qv), apparently tried to extort money from Cloncurry in return for pleading his case to the duke of Portland (qv); he refused the offer. On his release he toured England on horseback but was rearrested on 14 April 1799 and held until March 1801. His father voted for the act of union, hoping to secure his son's release, and died on 28 August 1799, Valentine succeeding as 2nd Baron Cloncurry. His grandfather and his fiancée, Mary Ryal, also died while he was imprisoned.
Embittered by his experience, he toured the Continent (1801–5) before returning to his family estate at Lyons, Co. Kildare. Throwing himself into improving his estates and into local concerns, he founded the County Kildare Farming Society (1814). He was also involved in canal developments and agricultural improvements in the country. Opposed to the rural constabulary bill of 1822, he supported catholic emancipation and the attempts of Daniel O'Connell (qv) to repeal the act of union. He broke with O'Connell in the 1830s when his friend Henry Paget (qv), marquess of Anglesey, was viceroy, because he believed repeal could now be achieved through official means; the rift was never healed. In 1831 he became an Irish PC and an English peer, but rarely attended the house of lords. Involved in anti-tithe campaigns, he retired from politics in 1840. Travelling on the Continent (1841–2), he returned to defend O'Connell's planned Clontarf meeting in the privy council (1843), but refused to attend any further meetings after his advice on dealing with the great famine was ignored in 1846. In 1849 he published his Personal reminiscences, which appear to have been ghost-written.
He died 28 October 1853, after catching a cold, and was buried at the family vaults at Lyons. He married first (16 April 1803) Elizabeth Georgiana, youngest daughter of Maj.-gen. George Morgan, at Rome; they had one son (d. 1825) and one daughter. The marriage ended in divorce in 1811 after her adultery with Sir John Piers; Cloncurry had already been awarded £20,000 in compensation in 1807. He married secondly (1811) Emily, daughter of Archibald Douglas of England, and widow of Joseph Leeson; they had two sons and a daughter. The elder son, Edward (1816–69), succeeded as 3rd Baron Cloncurry; the younger, Cecil-John (1820–53), was an MP, but caught a chill at his father's funeral and died 5 November 1853.