Having received his license, Broadhead began a private practice in 1842 at Bowling Green, Missouri.

From 1850 until 1853 he also served in the Missouri Senate before returning to private practice as a partner in a law firm back in St Louis.

[1] Attending the Missouri State Constitutional Convention in 1875, Broadhead worked closely on the Whisky Ring bribery cases in 1876.

During his campaign for Congress in 1882, the St. Louis Post-Dispatch began running articles critical of Broadhead at the direction of John Cockerill, the managing editor.

Cockerill shot and killed Slayback, claiming self-defense, and a grand jury refused to indict him.