In 1841, Lawrence moved to Bellefontaine, Ohio, and there set up his law practice. From July 15, 1841 to July 15, 1843 he was law partner of Benjamin Stanton, and from July, 1851 to February, 1854 with his law student William H. West. From 1841 to 1843, he continued his studies, then in the field of medicine. In 1842, he became the Commissioner of Bankruptcy for Logan County. From 1845 to 1847, Lawrence served as the editor of the Logan Gazette, which later became the Bellefontaine Examiner. During this time, Lawrence was elected as the Logan County Prosecutor. He also served as a member of the Ohio House of Representatives, in 1846 and 1847. In 1849, Lawrence was first elected to the Ohio Senate, serving until 1851 when he became the reporter of the Ohio Supreme Court. He returned to the Ohio Senate in 1854. He also served as an editor of Western Law Monthly from 1859 to 1862. In 1860 or 1861, Lawrence built a house along North Main Street in Bellefontaine; today, the William Lawrence House remains largely intact and is listed on the National Register of Historic Places.
In 1857, Lawrence was appointed Judge of the Court of Common Pleas and of the District Court, serving until he resigned in 1864. In 1862, he entered the Union Army as colonel of the 84th Ohio Infantry, a three-month regiment. In 1863, Lawrence was appointed to serve as the wartime judge for the United States district court in Florida; however, he declined the appointment.
Congressman and national political figure
On March 4, 1865, William Lawrence was inaugurated as the U.S. Representative for the 4th district of Ohio, having been elected to this office the previous November. He supported the adoption of the Fifteenth Amendment, stating in an 1866 speech that it would "protect every citizen, including the millions of people of foreign birth who will flock to our shores to become citizens and to find here a land of liberty and law." Lawrence served in the Thirty-ninth, Fortieth, and Forty-first Congresses, ending his third term on March 3, 1871. As Representative, Lawrence was among the authors of the bill of impeachment against U.S. President Andrew Johnson in 1868.
In 1867, as a member of the House Judiciary Committee, Lawrence directed an inquiry into the creation of a "law department" headed by the Attorney General and composed of the various department solicitors and district attorneys. On February 19, 1868, Lawrence authored the bill that ultimately created the United States Department of Justice. However, this first bill died in Congress due to the Congress's concern with the impeachment of President Johnson. In the following Congress, the issue was brought back to the table. Representative Thomas Jenckes of Rhode Island introduced a bill to create the Department of Justice on February 25, 1870. Though Lawrence did not write this bill, it incorporated many of the ideas from Lawrence's previous bill, and he gave the bill his full support. On June 22, 1870, President Ulysses Grant signed this second bill into law, creating the Department of Justice.
To Bellefontaine, and back to Washington
Returning to Bellefontaine in 1871, Lawrence founded the Bellefontaine National Bank, and served as its first president. He returned to Congress in 1873, this time from the 8th Ohio Congressional district. Lawrence served in the Forty-third and Forty-fourth Congresses, and completed his fifth and final term on March 3, 1877. During this service, Lawrence was the chairman of the Committee on War Claims arising from the American Civil War.
Lawrence was appointed by President Rutherford B Hayes in 1880 to serve as the First Comptroller of the Treasury, a post he held until 1885. Lawrence then appealed on behalf of Clara Barton to Hayes' successor, James Garfield, to support the creation of the American Red Cross on May 21, 1881. He then served as the organization's first Vice President. Lawrence and Barton were also instrumental in persuading the United States to ratify the Geneva Convention in 1882. In 1891, Lawrence was appointed President of the National Wool Growers Association. He died on May 8, 1899 in Kenton, Ohio. Lawrence is interred at Bellefontaine Cemetery in Bellefontaine, Ohio. The small Ohio community of Lawrenceville is named for him.
