The Office of the Public Protector has had to spend more than R15-million over the last four financial years to defend various reports that have been taken on judicial review, MPs heard on Tuesday.

Public Protector Busisiwe Mkhwebane appeared before the Portfolio Committee on Justice on Tuesday to present her department's strained budget for the current financial year.

She said her office drastically needed an improved budget because they were operating with a cumulative shortfall of R29-million, built up since 2013. She has asked for a R285-million budget in 2018/19, and R870-million over the next three years.

Her predecessor Thuli Madonsela, had also frequently requested more money to continue operational projects in the office during her tenure.

Contributing to the shortfall was the costs of defending 18 different published reports that have been taken on judicial review by various complainants since the 2013/14 financial year. It included Madonsela's period in office.

Of those, four reports were taken on review in 2014, one in 2015, and six in 2016. A further seven have been taken on review since Mkhwebane took office at the end of 2016.

The biggest contributor to the R15-million figure was the approximately R88-million spent during a review of her controversial Absa/CIEX report, which was eventually set aside by the North Gauteng High Court in Johannesburg in February.

Other costly defences include the judicial review of Madonsela's State of Capture report, launched by former President Jacob Zuma and others, totaling R1.9-million.

Also included is R739 000 spent in court defending Madonsela's Derailed report into board irregularities at Prasa, launched by former CEO Lucky Montana.

The majority of reviews launched since 2017 have not yet cost the office any legal fees because they were still in process, she said.

This included the report into the Vrede dairy matter, which the Democratic Alliance (DA) took on review earlier this year.

National Treasury had helped her office with the R15-million deficit but nonetheless, the call for a new funding structure was warranted, she pleaded.

Her office also needed a further R26-million to improve their case management system in 2018/19.

MPs noted that a good portion of the shortfall was largely due to the litigation against reviews.

"We know that many of the reviews emanate from the time of your predecessor, but [nonetheless] your office currently has between 15 and 20 matters currently on review," DA MP Glynnis Breytenbach said.

"To spend R8-million in one court case is a very substantial amount," African Christian Democratic Party MP Steve Swart added.

Parliament goes into its second term reviewing performance plans and annual budgets for all state departments and entities.

New budgets for those departments and entities are approved and voted on in the National Assembly closer to the end of the term in June.

Meanwhile, MPs were expected to pose more questions to Mkhwebane on Tuesday about her budget and other matters.