Dickey was born on October 18, 1823, probably in Grayson County. He was the son of James Dickey and his first wife, Elizabeth Bourne Dickey. Late in the 1840s he married Martha Hale. They had at least two daughters and one son. Dickey owned nearly 300 acres of land near the courthouse in the town of Independence and was identified as a farmer both before and after the Civil War. He also worked at the county courthouse as clerk of court in 1851. He may have remained at home working his farm during the Civil War. In July 1866 Dickey petitioned theto commute the death sentence of an African American to life imprisonment, on the grounds he did not receive a fair trial because of the prejudices of some civil officers of the county court.
On October 22, 1867, Dickey was one of two men elected to represent Carroll, Floyd, and Grayson counties in the state constitutional convention that met from December 3, 1867, to April 17, 1868. Incomplete election returns indicate that he received significant support from African American men, who were eligible to vote for the first time. He served as ranking member of the Committee on Taxation and Finance, but he did not speak during the portion of the convention for which a record of debates survives. Dickey was sympathetic to the state’s new Republican Party but frequently sided with Conservatives during roll-call votes. Although he opposed theof blacks, he also voted against restrictions on the suffrage of former secessionists and supported racial segregation in the new public school system. On April 17 he voted against the constitution that the convention adopted. In 1868 Dickey sold some land for the establishment of an African American school in Independence. The following year he received $30 for repairs and sat on the county board of education during the first years of the school system.
Dickey was active in the Grayson County Republican Party during the 1870s and 1880s. He helped found one partisan newspaper in Independence, the Grayson Journal, and with several partners bought another paper, the Grayson Clipper, and transformed it into another Republican Party organ. He served as deputy collector of internal revenue during the second presidential administration ofand postmaster of the town of Independence from July 1889 to April 1893, during the administration of Benjamin Harrison. Dickey joined most other Virginia Republicans during the 1880s in supporting the , a biracial coalition that sought to repudiate a portion of the and to redirect remaining resources in support of public schools and other state institutions. Early in 1876 he formed a partnership to open a mine in the county, but his business and financial history, as well as his personal history, is poorly documented.
By the end of the century, Dickey and his wife had moved into the household of one of their married daughters in Independence. Dickey died on January 28, 1903, and was buried in the Independence town cemetery.