Senator Bartle was born and raised in Columbia, Missouri. He graduated from the University of Missouri, Columbia, with a bachelor's degree in Economics in 1987. In 1990, Senator Bartle graduated from the Northwestern University School of Law in Chicago, Illinois. Upon graduation from law school, he completed a one-year judicial clerkship for the Honorable W. Eugene Davis of the United States Court of Appeals for the Fifth Circuit. Senator Bartle began his legal career with Bryan Cave LLP. In 1998, he joined Berkowitz Oliver Williams Shaw & Eisenbrandt, LLP. He is currently with Graves, Bartle, Marcus and Garrett LLC in Kansas City.

Senator Bartle was elected to the Missouri House of Representatives in 1998 and again in 2000. He served on both the House Judiciary and Criminal Law Committees. In 2002, the people of the 8th Senatorial District, which includes all of Eastern Jackson County, elected him as state senator, and re-elected him in 2006. Senator Bartle is chairman of the Senate Judiciary, Civil and Criminal Law Committee. His is also a member of the Senate’s Commerce, Consumer Protection and the Environment Committee, the Financial and Governmental Organizations and Elections Committee, and the Ways and Means Committee.

During his tenure in the Missouri General Assembly, Senator Bartle has been a leader on issues related to civil and criminal law and on the functioning of Missouri's judicial system in general. Working with judges from all levels, Senator Bartle chaired the Joint Interim Committee on Judicial Resources which made recommendations on reallocating judicial resources in the state. Senator Bartle has been the lead sponsor of major reforms in Missouri law including the 2004 Missouri Securities Act, Missouri's DNA Database and the Internet Sex Offender Registry.

Senator Bartle and his wife, Annette, have been married for 16 years. They have a son, Mack, and a daughter, Betsy.