Before being elected to the Missouri Senate, Sen. May served as state representative for the 84th District in the Missouri House of Representatives. First elected in 2010, she served eight years in the Missouri House. As a state representative, she served on the Budget and Transportation committees. She was also the ranking minority member of both the Subcommittee on Appropriations - Public Safety, Corrections, Transportation and Revenue and the Special Committee on Employment. She formerly served as the vice chair of the Missouri General Assembly's Black Legislative Caucus; treasurer of the bipartisan Missouri Women's Legislative Caucus; and has served as a member of the Budget and Revenue Committee for the National Conference of State Legislatures. Senator May served as the Region XI chair for the National Black Caucus of State Legislators from 2012-2018, serving Iowa, Kansas, Missouri and Nebraska, formerly serving on the Executive Committee as chaplain and currently serving as an at-large member.

Currently, Sen. May is the Minority Caucus chair and serves on Appropriations; Commerce Consumer Protection, Energy and the Environment; Judiciary and Civil and Criminal Jurisprudence; Rules, Joint Rules, Resolutions and Ethics; Joint Committee on Child Abuse & Neglect; Joint Committee on the Justice System; Joint Committee on Public Assistance; Task Force on Substance Abuse Prevention and Treatment; Interim Committee on Elections; Interim Committee on Greater St. Louis Regional Emerging Issues; Interim Committee on Medicaid Accountability and Taxpayer Protection and also appointed by the governor to the Missouri Justice Reinvestment Initiative.

Aside from her legislative duties, Sen. May is president and board member of the St. Louis Philanthropic Organization. She has been involved with the organization for the past 25 years, helping award grants to agencies focused on education and programs that benefit the residents of the City of St. Louis. She is an executive board member of the Coalition of Black Trade Unionists (CBTU) St. Louis Chapter and serves as an international at-large board member.

Born and raised in the City of St. Louis, Sen. May currently resides in the city's 26th Ward, and has been employed with AT&T for 25 years. She attends Grow 2 Go (G2G) Christian Center (formerly St. Louis Christian Center) where she has served as youth minister since October of 2001, serves on the Pastor's Think Tank, outreach ministry and the intercessory prayer ministry. She holds an ASBA from Forest Park Community College and a BSBA from Saint Louis University.