He was first seated by Congress in 1890 after it found in his favor in relation to the contested 1888 election in Maryland's 5th congressional district, which was marked by fraud and intimidation.

[1] He was born into the planter class at the family plantation, Gallant Green, in Charles County, Maryland, Mudd was reared Catholic and first educated locally.

He was the nephew of Samuel Mudd, the doctor that aided John Wilkes Booth after he assassinated President Abraham Lincoln.

[5] As a Republican candidate, he challenged and successfully contested the 1888 election of Barnes Compton as US Representative from the 5th district to the Fifty-first Congress.

He claimed that election officials had turned away qualified voters and that, in Anne Arundel County, Democrats posing as US Marshals intimidated blacks, forcing them from the polls.

[5] In 1896 Mudd benefitted by the coattails of a winning Republican biracial coalition that gained the governorship.