Maseko was born on 2 March 1958 in Alexandra township outside Johannesburg in the Transvaal, now part of Gauteng province.

[3] Pursuant to the 2009 general election, Maseko was re-elected to a fourth term in her seat in the provincial legislature and was elected Speaker of the Gauteng Provincial Legislature under Nomvula Mokonyane, the new Premier of Gauteng.

[8] The first woman to hold the position,[3] she was deputised by Steward Ngwenya and, from August 2012, by Uhuru Moiloa.

[11] Maseko's conduct in both episodes was subject to investigation by the Gauteng Integrity Commissioner, Ralph Mgijima, and by the Privileges and Ethics Committee of the provincial legislature.

Both investigations cleared her of personal wrongdoing, finding that she had not contravened the provincial ministerial code nor indulged in exorbitant or frivolous spending: she had not directly influenced the selection of the caterer for the legislative opening, and a six-month stock of groceries had been bought for her office due to poor supply chain management and record-keeping.

[13] In January 2022, she – alongside Ronald Lamola, Jeff Radebe, and Joel Netshitenzhe – was appointed by President Cyril Ramaphosa to serve on an internal ANC committee which was tasked with guiding the ANC's response to the findings of the Zondo Commission.