In 1917 he joined the United States Army and during the First World War he became a first lieutenant. After leaving the army he joined his friend, Sid Richardson, as a lease trader in the Burkburnett oilfield. According to Ernestine Orrick Van Buren, the author of Clint: Clint Williams Murchison (1986): "He quickly moved into exploration and development, and despite the fluctuations in the price of oil, he sold his holdings in 1925 for $5 million and moved his base of operations to San Antonio."
Texas oil millionaires such as Murchison, fought hard to maintain its tax concessions. The most important of these was the oil depletion allowance. It allowed producers to use the depletion allowed to deduct just 5 per cent of their income and the deduction was limited to the original cost of their property. However, in 1926 the depletion allowance was increased to 27.5 per cent. As Robert Bryce pointed out in his book, Cronies: Oil, the Bushes, and the Rise of Texas, America's Superstate: "Numerous studies showed that the oilmen were getting a tax break that was unprecedented in American business. While other businessmen had to pay taxes on their income regardless of what they sold, the oilmen got special treatment."
In 1929 Murchison formed the Southern Union Gas Company. Over the next few years the company supplied natural gas throughout Texas, Oklahoma, Arkansas, Arizona, and New Mexico. On 3rd October 1930 Columbus Joiner discovered oil eight miles west of Henderson, Texas. Murchison invested heavily in this oilfield and built the Tyler Pipe Line to deliver crude oil to a new refinery in Tyler. Murchison then sent the oil by rail to Houston for distribution throughout the world. An opponent of government regulation of private industry, he named his new corporation American Liberty Oil Company.
Jane Wolfe, the author of The Murchisons: The Rise and Fall of a Texas Dynasty (1989) has argued: "Clint Murchison by now had made $20 to $30 million, some from drilling but chiefly from oil leases and pipelines. His next step was much riskier and potentially much more profitable - drilling oil wells on a massive scale... Murchison had been thinking about, and calculating again and again, the profit posibilities that derived from the combination of two extraordinary tax advantages available to oil producers." One of these was the oil depletion allowance. The second issue was what became known as oil payment: "The other extraordinary tax advantage enjoyed by oil producers was the so-called oil payment, a method of borrowing enormous sums for exploration and drilling, while simultaneously avoiding any income tax at all on oil income."
Ernestine Orrick Van Buren pointed out: "In the late 1930s Murchison began diversifying his investments. He acquired numerous life-insurance companies, banks, bus lines, publishing firms, heavy industrial building materials companies, and an assortment of companies serving such leisure activities as hunting, fishing, travel, and gardening. He was a cattleman throughout his life and acquired extensive ranches in Mexico and East Texas. He experimented in improving cattle strains and in developing superior grazing grasses."
In 1945 Murchison established Delhi Oil Corporation. His greatest asset was the gas reserves developed by its subsidiary, Canadian Delhi, in western Canada. Murchison developed the 2,100-mile Trans-Canada Pipe Line that after delivered natural gas from the fields of Alberta to the eastern seaboard. Murchison also developed gas reserves in Australia and another one of his business ventures was the Florida Gas Company, which transported gas from points along the Texas coast to cities in Florida.
Murchison, along with Sid Richardson and Haroldson L. Hunt, became major supporters of Lyndon B. Johnson in order to maintain the oil depletion allowance. According to Robert Bryce: "Johnson's 1948 race was reportedly the most expensive political campaign ever wages in Texas. The money flowed to Johnson like an inexhaustible river. By befriending Richardson, Murchison, Hunt, and other oilmen like Amon Carter of Fort Worth, Wesley West of Austin, and R. J. Parten of Houston, Johnson assured himself of nearly unlimited funding."
Philip F. Nelson, the author of LBJ: The Mastermind of the JFK Assassination (2011) has pointed out that the oil depletion allowance, "allowed them to retain 27.5 percent of their oil revenue tax-tree; its loss, according to World Petroleum magazine, stood to cost the industry as much as $280 million in annual profits. The original rationale for such an allowance was that the product that their investments yielded yeas a finite resource that would require continual investments in exploration and recovery in order to extend the flow of raw material; the more the companies produced, the less was available. Recognition of this depletion of the asset was intended as an incentive for finding and recovering more oil fields. (How this particular commodity was materially different from other forms of mining, or commercial ocean fishing, or even farming, was never fully explained, other than perhaps the oilmen having better lobbyists than the others.)"
Murchison and Sid Richardson, became friends of J. Edgar Hoover, the head of the Federal Bureau of Investigation. It was the start of a long friendship. According to Anthony Summers, the author of The Secret Life of J. Edgar Hoover (1993): "Recognizing Edgar's influence as a national figure, the oilmen had started cultivating him in the late forties-inviting him to Texas as a houseguest, taking him on hunting expeditions. Edgar's relations with them were to go far beyond what was proper for a Director of the FBI."
Hoover and his friend, Clyde Tolson, were regular visitors to Murchison's Del Charro Hotel in La Jolla, California. The three men would visit the local racetrack, Del Mar. Allan Witwer, the manager of the hotel at the time, later recalled: "It came to the end of the summer and Hoover had made no attempt to pay his bill. So I went to Murchison and asked him what he wanted me to do." Murchison told him to put it on his bill. Witwer estimates that over the next 18 summers Murchison's hospitality was worth nearly $300,000. Other visitors to the hotel included Richard Nixon, John Connally, Lyndon B. Johnson, Meyer Lansky, Santos Trafficante, Johnny Rosselli, Sam Giancana and Carlos Marcello.
In 1952 Hoover and Murchison worked together to mount a smear campaign against Adlai Stevenson, the Democratic Party candidate for the presidency. Hoover and his friend, Clyde Tolson, also invested heavily in Murchison's oil business. In 1954 Murchison joined forces with Richardson and Robert Ralph Young to gain control of the New York Central Railroad. This involved buying 800,000 shares worth $20 million.
Clint Murchison was also closely liked to the Mafia. In 1955 a Senate committee discovered that 20 per cent of the Murchison Oil Lease Company was owned by Vito Genovese and his family. The committee also discovered Murchison had close financial ties with Carlos Marcello. Later, Bobby Baker claimed that. "Murchison owned a piece of Hoover. Rich people always try to put their money with the sheriff, because they're looking for protection. Hoover was the personification of law and order and officially against gangsters and everything, so it was a plus for a rich man to be identified with him. That's why men like Murchison made it their business to let everyone know Hoover was their friend. You can do a lot of illegal things if the head lawman is your buddy."
In 1958 Murchison purchased the publishers, Henry Holt and Company. He told the New York Post: "Before I got them, they published some books that were badly pro-Communist. They had some bad people there.... We just cleared them all out and put some good men in. Sure there were casualties but now we've got a good operation." One of the first book's he published was by his old friend, J. Edgar Hoover. The book, Masters of Deceit: The Story of Communism in America (1958), was an account of the Communist menace and sold over 250,000 copies in hardcover and over 2,000,000 in paperback. It was on the best-seller lists for thirty-one weeks, three of them as the number one non-fiction choice.
William Sullivan was ordered to oversee the project, claimed that as many as eight agents worked full-time on the book for nearly six months. Curt Gentry, the author of J. Edgar Hoover: The Man and the Secrets (1991) points out Hoover claimed that he intended to give all royalties to the FBI Recreational Association (FBIRA). However, he claims that the "FBIRA was a slush fund, maintained for the use of Hoover, Tolson, and their key aides. It was also a money-laundering operation, so the director would not have to9 pay taxes on his book royalties." Gentry quotes Sullivan as saying that Hoover "put many thousands of dollars of that book.... into his own pocket, and so did Tolson."
Murchison developed extreme right-wing political opinions and along with his friend, Haroldson L. Hunt, was a supporter of the John Birch Society. Murchison funded the anti-communist campaign of Joseph McCarthy. It was claimed that McCarthy got so much money from the Lone Star State he became known as "the third senator from Texas". According to Anthony Summers, Murchison was also "a primary source of money for the American Nazi Party, and its leader, Lincoln Rockwell".
In 1955 Lyndon B. Johnson became majority leader of the Senate. Johnson and Richard Russell now had complete control over all the important Senate committees. This was proving to be an expensive business. The money used to bribe these politicians came from Russells network of businessmen. These were men usually involved in the oil and armaments industries. According to John Connally, large sums of money was given to Johnson throughout the 1950s for distribution to his political friends. I handled inordinate amounts of cash. A great deal of this came from oilmen like Murchison.
In 1956 there was another attempt to end all federal price control over natural gas. Sam Rayburn played an important role in getting it through the House of Representatives. This is not surprising as according to Connally, he alone had been responsible for a million and a half dollars of lobbying. Paul Douglas and William Langer led the fight against the bill. Their campaigned was helped by an amazing speech by Francis Case of South Dakota. Up until this time Case had been a supporter of the bill. However, he announced that he had been offered a $25,000 bribe by the Superior Oil Company to guarantee his vote. As a man of principal, he thought he should announce this fact to the Senate.
Johnson responded by claiming that Case had himself come under pressure to make this statement by people who wanted to retain federal price controls. Johnson argued: In all my twenty-five years in Washington I have never seen a campaign of intimidation equal to the campaign put on by the opponents of this bill. Johnson pushed on with the bill and it was eventually passed by 53 votes to 38. However, three days later, Dwight D. Eisenhower, vetoed the bill on grounds of immoral lobbying. Eisenhower confided in his diary that this had been the most flagrant kind of lobbying that has been brought to my attention. He added that there was a great stench around the passing of this bill and the people involved were so arrogant and so much in defiance of acceptable standards of propriety as to risk creating doubt among the American people concerning the integrity of governmental processes.
Murchison and Sid Richardson began negotiations with President Eisenhower. In June, 1957, Eisenhower agreed to appoint their man, Robert Anderson, as his Secretary of the Treasury. According to Robert Sherrill in his book, The Accidental President: "A few weeks later Anderson was appointed to a cabinet committee to "study" the oil import situation; out of this study came the present-day program which benefits the major oil companies, the international oil giants primarily, by about one billion dollars a year."
According to Jane Wolfe, the author of The Murchisons: The Rise and Fall of a Texas Dynasty (1989), Murchison's relationship with Lyndon B. Johnson came to an end when he accepted the offer to be the running-mate of John F. Kennedy: "Many of Texas's richest oilmen had supported Johnson for years with large contributions, but when he accepted the vice presidency under Kennedy, they felt betrayed. Johnson had enormous clout in the Senate, and much of this power was due to these Texas oilmen. During the fifties LBJ breakfasts at Clint's Preston Road home were commonplace. The Texas senator and ten or twelve of the state's richest oilmen would gather for coffee on the front porch, while Johnson gave an overview of what might happen in Congress affecting the oil industry and of the coming election. Johnson would announce which senators needed money and just how much they needed to defeat their opponents. Then Clint Murchison would assign the fund-raising job to one of the men gathered at the breakfast... In return, Johnson was expected to deliver the vote on the depletion allowance, and all other legislation of interest of the oilman."
On 16th October, 1962, President Kennedy was able to persuade Congress to pass an act that removed the distinction between repatriated profits and profits reinvested abroad. While this law applied to industry as a whole, it especially affected the oil companies. It was estimated that as a result of this legislation, wealthy oilmen saw a fall in their earnings on foreign investment from 30 per cent to 15 per cent. The following year, on 17th January, 1963, President Kennedy presented his proposals for tax reform. This included relieving the tax burdens of low-income and elderly citizens. Kennedy also claimed he wanted to remove special privileges and loopholes. He even said he wanted to do away with the oil depletion allowance. It is estimated that the proposed removal of the oil depletion allowance would result in a loss of around $300 million a year to Texas oilmen.
Rumours began to circulate that Murchison might have been involved in the assassination of John F. Kennedy. A friend of Murchison, Madeleine Brown, claimed in an interview on the television show, A Current Affair that on the 21st November, 1963, she was at his home in Dallas. Others at the meeting included Haroldson L. Hunt, J. Edgar Hoover, Clyde Tolson, John J. McCloy and Richard Nixon. At the end of the evening Lyndon B. Johnson arrived. Brown said in this interview: "Tension filled the room upon his arrival. The group immediately went behind closed doors. A short time later Lyndon, anxious and red-faced, reappeared. I knew how secretly Lyndon operated. Therefore I said nothing... not even that I was happy to see him. Squeezing my hand so hard, it felt crushed from the pressure, he spoke with a grating whisper, a quiet growl, into my ear, not a love message, but one I'll always remember: "After tomorrow those goddamn Kennedys will never embarrass me again - that's no threat - that's a promise."
Gary Mack has argued that this party never took place: "Could LBJ have been at a Murchison party? No. LBJ was seen and photographed in the Houston Coliseum with JFK at a dinner and speech. They flew out around 10pm and arrived at Carswell (Air Force Base in northwest Fort Worth) at 11:07 Thursday night. Their motorcade to the Hotel Texas arrived about 11:50 and LBJ was again photographed. He stayed in the Will Rogers suite on the 13th floor and Manchester (William Manchester - author of The Death of a President) says he was up late. Could Nixon have been at Murchisons party? No. Tony Zoppi (Entertainment Editor of The Dallas Morning News) and Don Safran (Entertainment Editor of the Dallas Times Herald) saw Nixon at the Empire Room at the Statler-Hilton. He walked in with Joan Crawford (Movie actress). Robert Clary (of Hogans Heroes fame) stopped his show to point them out, saying . . . either you like him or you dont. Zoppi thought that was in poor taste, but Safran said Nixon laughed. Zoppis deadline was 11pm, so he stayed until 10:30 or 10:45 and Nixon was still there."