The Zimbabwe Human Rights NGO Forum has filed an urgent chamber application seeking an order for Chief Justice Malaba to resign by 15 May 2021.
This comes after the Zanu PF led government railroaded its legislators to pass the controversial Constitutional Amendment Bill No.2 into law whose effect was to increase the retirement age of serving judges.
Critics insist the law, signed into an Act at breakneck speed by President Emmerson Mnangagwa last week, was tailored to elongate Malaba's tenure as head of the Zimbabwean bench.
Malaba has a special space in Zanu PF hearts after he ruled in favour of Mnangagwa, whose victory in the 2018 elections was challenged through the Constitutional Court by his main rival, Nelson Chamisa of MDC Alliance.
However, according to the order sought by the NGO Forum, any action taken by Malaba after midnight of 15 May should be deemed null and void.
The application is based on the legal grounds that the recent amendments to the constitution cannot benefit Chief Justice Malaba.
Section 328 of the constitution that deals with tenure of judges cannot be amended without a referendum.
"It is also the fault of the second respondent (Chief Justice Malaba) who by now should have proceeded on leave to allow for a smooth hand over and takeover.
"There was such a smooth handover and takeover when his predecessor left office. There has been no movement from second respondent's end even before the bill was signed into law.
"The impression created is that he had waited for the bill to be signed into law."
However, the challenge by the rights group sets the proverbial cat among the pigeons as it would be very unlikely for Malaba's juniors within Zimbabwean courts to rule against their boss.
This follows concerns the country's top jurist has an overbearing influence over the outcome of a lot of court cases that fall into his subordinates' in-trays.
In October last year, the country's High Court and Supreme Court judges hit out at "manipulative" Malaba in a stinging letter addressed to President Emmerson Mnangagwa.
In the letter of complaint, the judges revealed morale was at an all-time low within the judiciary over Malaba's alleged interference with their work.
They also accused the judiciary chief of employing an overplaying hand regarding court judgements, adding that many of them were operating in fear of being victimised instead of being objective.
"What is reported in the public domain and on social media about the capture of the judiciary is no longer fiction or perception, it is in fact reality," the judges said in their no-holds-barred letter.