Before being elected to the Missouri Senate, Senator 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 & 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 and currently serves on the Executive Committee as Chaplain.

Aside from her legislative duties, Senator May is President and Board Member of the St. Louis Philanthropic Organization. She has been involved with the organization for the past 21 years, helping award grants to agencies focused on education and programs that benefit 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 has served as an international at-large board member.

Born and raised in the City of St. Louis, Senator May currently resides in the city's 26th Ward.