The Pakatan Rakyat (PR) coalition is calling for Malaysia's police chief to be censured by Parliament for the ongoing crackdown on opposition figures following Anwar Ibrahim's Feb 10 jailing for sodomy.
Among those detained is Anwar's daughter, lawmaker Nurul Izzah Anwar, who was released by police yesterday.
Opposition leader Anwar's controversial conviction - which he says is a political conspiracy to undermine his PR coalition - has been followed by strident criticism of the authorities and a series of gatherings culminating in the March 7 rally in Kuala Lumpur that drew thousands of his supporters.
Lembah Pantai MP Nurul Izzah spoke in Parliament last week, accusing the Federal Court judges who sentenced Anwar to five years' jail of "selling out to the devil". The speech led to her arrest under the Sedition Act on Monday, despite claims that such an investigation contravened the rights of a federal lawmaker.
Police have arrested at least 10 people in relation to the March 7 protest, despite the Court of Appeal declaring last year that the Peaceful Assembly Act was unconstitutionally criminalising public gatherings.
Sedition probes on a political cartoonist and six opposition leaders, including Ms Nurul Izzah, have also been initiated.
This led to PR's decision yesterday to draft and table a motion sanctioning Inspector-General of Police (IGP) Khalid Abu Bakar for undermining the Court of Appeal and the integrity of Parliament.
Ms Nurul Izzah told a press conference that she hoped the move would help "inculcate an understanding in Malaysia's top cop on the concept of separation of powers in this country".
Her opposition colleague and veteran MP Lim Kit Siang also accused Tan Sri Khalid of violating parliamentary privileges and immunity. "He is not fit to be an IGP," he said.
The move comes as the police investigation of opposition figures continued unabated.
Another member of Anwar's own party, Parti Keadilan Rakyat, was arrested yesterday, while one of Ms Nurul Izzah's sisters, Ms Nurul Nuha Anwar, was also told to report for questioning, both in connection with the March 7 protest.
Although the motion censuring the police chief will likely fail, it could add fuel to the opposition's claims that the government is silencing dissent and aborting a reform package that Prime Minister Najib Razak announced when he came to power in 2009.
Critics have complained that the vague definition of offences under the Sedition Act has led to abuse by the government to clamp down on critics.
Datuk Seri Najib had pledged in 2012 to repeal the law, but backtracked last year after his ruling Umno party called for the Act to be further strengthened to protect national harmony and the special position of Islam and the Malay ethnic majority.
Anwar's daughter now a symbol of reform
Ms Nurul Izzah Anwar shot to fame as a fresh-faced 18-year-old "Puteri Reformasi" (Princess of Reformation) after her father Anwar Ibrahim was sacked as deputy prime minister in 1998.
The political upheaval from Anwar's sacking and subsequent jailing for abuse of power and sodomy sparked street riots and galvanised a previously hapless opposition.
Now 35 and a second-term MP, Ms Nurul Izzah spearheaded a campaign for her father's release and the sodomy conviction was overturned in 2004, allowing Anwar, who was jailed again on a new sodomy charge last month, to lead the Pakatan Rakyat opposition coalition to record electoral gains in the 2008 and 2013 general elections.
In these polls, Ms Nurul Izzah was an iconic giant-killer, vanquishing two sitting Cabinet ministers to win the Lembah Pantai constituency.
Many, including her mother, describe her as having inherited her firebrand father's stubbornness - and also his charisma.
She is now a potent symbol of the opposition's reform platform, promising a place for young and idealistic voices. Even a divorce that dragged on in court for a year until January this year has failed to dent her popularity.
Seen by some as a future prime minister, her arrest yesterday led to widespread condemnation of the authorities.
She is already vice-president of Parti Keadilan Rakyat, the young party born of the Reformasi movement in 1998, but the challenge for her now is to step out of her father's shadow and push forward without his guidance.