A judge meted out a four-month jail sentence to a maid for ill-treating her four-year-old charge when she tried to retrieve a medical device from the boy's throat, saying she had no medical training and bore no malice.

District Judge Low Wee Ping had disagreed with the prosecution's call earlier this month for the maid to be jailed for 18 months, describing it then as "manifestly excessive".

Yesterday, he backdated Kusrini Caslan Arja's sentence to Nov 25, when she was first remanded, which allowed her to be released yesterday. But the prosecution will be appealing against the sentence. Pending the appeal, Kusrini, 37, will be staying at the Indonesian Embassy.

As she was unrepresented when she pleaded guilty on March 6, Judge Low had then asked for a lawyer in court to volunteer and represent her. Mr Mahmood Gaznavi offered his services.

Yesterday in court, the lawyer said Kusrinihad only six years of primary education and was not medically trained. He said that despite this,she was tasked with the care of the bedridden boy, and she received only two days of training from the boy's parents on how to operate a machine to suck phlegm from his windpipe.

Urging the judge to sentence her to four months in jail, the lawyersaid: "The present matter is akin to a specialist carpenter asked to perform complicated mechanical works.

"She is a person of no skills, let alone skills required to nurse a child who is bedridden."

In sentencing her, Judge Low said he agreed with Mr Gaznavi's mitigation plea in "almost every aspect".

The boy, who cannot be named because of a court order, has Type 1 spinal muscular atrophy and needs support ventilation and oxygen.

The boy's parents hired Kusrini in March last year and they trained her to use the machine, which includes a suction cap that is attached to a tube and is about the size of an adult's thumb. Kusrini was told to place the suction cap only outside the boy's nose and lips. But she failed to follow the instructions at around 9am on Nov 23 last year.

The mother of two girls, aged two and 12, inserted the cap into the boy's mouth because she felt it would work faster. But when she inserted her fingers about a minute later to remove the cap, she realised it was not there. She panicked and, for eight minutes, she continuously inserted her right hand into the boy's mouth to try to fish it out, but failed.

Closed-circuit TV camera footage showed she did not stop when his face turned purple and when her hand was smeared with blood from his mouth.

Her offences came to light only after the couple returned at 7pm.

Deputy Public Prosecutor Teo Lu Jia said the boy's mother, a nurse, removed the cap from his throat about 12 hours after it fell in. The boy was rushed to KK Women's and Children's Hospital, where cuts were found inside his throat. He was discharged two days later.

Yesterday, DPP Teo said: "(Kusrini) had deliberately decided not to seek help from anyone or inform the victim's parents, and to allow the suction cap to remain lodged in the victim's throat in spite of the suffering occasioned to the child and the risk to his safety."

But Mr Gaznavi said no malice was involved in his client's case. Highlighting that she came from a village and had never left Indonesia before coming to Singapore, he added: "She ought to have sought assistance. She ought to have called an ambulance. She ought to have dialled 995. But this was a person immersed in panic. She was enveloped by fear."

Judge Low agreed with the defence.

Mr Gaznavi told the court that he worked on the case with another lawyer, Mr Raeza Ibrahim from Drew and Napier, who had also volunteered to help the maid.

Speaking to reporters outside the courtroom, Mr Gaznavi said: "My client is relieved and is sorry for what happened. She just wants to go back to Indonesia."

For ill-treating the boy, Kusrini could have been jailed for up to four years and fined up to $4,000.