Property agent Daliana Abdullah was on Friday acquitted of maid abuse after inconsistencies emerged in the domestic worker's testimony.
The 44-year-old had been charged with slapping her Indonesian maid, pulling her hair and slamming her head against a wall.
But during the week-long trial, Ms Putri Andanari, 26, kept changing her account of how she was allegedly attacked at Ms Daliana's Tampines flat in late 2009.
District Judge Lim Tse Haw said these inconsistencies affected the credibility of her evidence.
"In order to find that the prosecution has proved its case against Ms Daliana beyond reasonable doubt, I must be satisfied that the evidence of Ms Putri is so compelling that a conviction could be based solely on it," the judge said.
The maid started working for Ms Daliana in September 2009 and claimed she was slapped a month later.
During the trial, she demonstrated the alleged abuse in court.
She showed how her employer had apparently grabbed hold of her T-shirt and slapped her cheek once with an open palm and once with the back of her hand.
However, when questioned by the prosecutor, the maid insisted she had been slapped both times with an open palm.
Ms Daliana's lawyers, Mr Subhas Anandan and Mr Noor Marican, told The Straits Times that she was very relieved at the acquittal.
However, her mother Maimunah Ahmad was fined $15,000 in January after pleading guilty to burning the domestic worker with a hot spoon and hitting her with clothes hangers and a ladle.
The 80-year-old wheelchair user was spared jail after the court heard she suffered from anaemia and severe osteoporosis, which had led to compression fractures in her vertebrae.