It initiated an investigation into the saga and provincial commissioner André Gaum said the probe was in response to several complaints from across the country.
Gaum said that Zille would have 21 days to respond.
“The complaint will not be investigated as hate speech, but as a potential violation of human dignity,” he added.
A storm erupted on March 15 after Zille sent out the following tweets in succession:
* Much to learn from Singapore, colo- nised for as long as SA, and under brutal occupation in WW2. Can we apply the lessons in our democracy?
* Singapore had no natural resources and 50 years ago was poorer than most African countries. Now they soar. What are the lessons?
* I think Singapore lessons are: 1) Meritocracy; 2) Multiculturalism; 3) Work ethic; 4) Open to globalism; 4) English. 5) Future orientation.
* Other reasons for Singapore’s success: Parents take responsibility for children, and build on valuable aspects of colonial heritage.
* For those claiming legacy of colonialism was ONLY negative, think of our independent judiciary, transport infrastructure, piped water etc.
* Would we have had a transition into specialised health care and medication without colonial influence? Just be honest, please.
* Getting onto an aeroplane now and won’t get onto the wi-fi so that I can cut off those who think EVERY aspect of colonial legacy was bad.
While Zille later apologised, the former DA leader was adamant her views on colonialism were misconstrued. She added that there were many “falsehoods” in relation to the series of tweets sent out on lessons learnt from her recent visit to Singapore.
“One of those lessons was that Singapore, having suffered centuries of colonial oppression, succeeded in re-purposing aspects of colonialism’s legacy on which they built an inclusive modern economy. This, among other things, has enabled its people to escape poverty within a generation,” Zille wrote in a letter.
She said on Thursday that she had not been contacted by the commission, but that “it’s fine” if it wished to investigate the matter.
Zille was formally charged last month with bringing the DA into disrepute and damaging the party.
The DA’s federal executive chairperson James Selfe said it was in contact with Zille to determine a date for her hearing.