Attorney-General Tommy Thomas will investigate why the charge against a senior citizen for the murder of a domestic worker was dropped, according to Bukit Mertajam MP Steven Sim.

This follows reports of 61-year-old MAS Ambika being granted a full acquittal by the Penang High Court over the killing of Indonesian national Adelina Lisao, despite the prosecution only seeking a discharge not amounting to an acquittal.

"I have contacted the attorney-general to seek clarification. The attorney-general has responded that he will personally investigate this matter to look into the next course of action," Sim said in a statement.

"I trust the attorney-general and the legal system will uphold justice. 

"I reiterate my stand that Malaysia needs better laws to protect migrant workers in this country."

Sim was among the first to highlight Adelina's plight early last year.

He provided photos of Adelina being forced to sleep at the front porch, along with the family dog.

The domestic worker was kept at the porch for a month, and suffered noticeable bruises on her body when she was rescued and rushed to the hospital on Feb 10, 2018.

Adelina died the next day. A postmortem attributed her death to multiple organ failure.

Aside from Ambika's murder charge, her daughter R Jayavartiny had also been charged for allegedly employing Adelina without valid documentation.