KPK investigators arrested Nurhadi and his son-in-law Rezky Herbiyono in South Jakarta on Tuesday – roughly six months after both were named suspects for allegedly accepting bribes in the form of nine checks and Rp 46 billion (US$3.2 million) in cash pertaining to three cases handled by the country's highest court between 2011 and 2016.

Many suspect that Nurhadi had been hiding in South Jakarta the entire time, raising suspicions that other parties were involved in protecting him from law enforcement. 

Haris Azhar, the executive director of legal and human rights group the Lokataru Foundation, said the KPK should look into the possibility others had played a role in hiding Nurhadi from the graft busters. Should anyone be found to have done so, the antigraft body could charge them with obstruction of justice, as stipulated in Article 21 of the 2001 Corruption Law. 

"Investigators should reveal whose houses were used [to hide Nurhadi], as well as any persons who assisted, protected or provided him with his daily needs during his time on the run," Haris said in a discussion on Friday.

Former KPK commissioner Bambang Widjojanto echoed Haris' statement, saying Nurhadi was able to move undetected for more than 100 days although he was just "an ordinary civil servant".

"The question is whether he has any extraordinary ability to evade arrest, or was someone in charge of protecting him?" said Bambang.

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Some have accused the KPK of hampering its own investigation into the case, saying the antigraft agency lacked the will and courage needed to expose other parties involved in the case.

Bambang claimed the KPK had ignored information provided by members of the public regarding Nurhadi’s whereabouts, including from Haris in February.

He also claimed the antigraft body had pursued a “judicial strategy” by putting the suspects on the most wanted list, meaning the KPK would not need to disclose information pertaining to the case if information was not provided by the public.

When asked whether the investigators would open an investigation into possible obstruction of justice, KPK chairman Firli Bahuri said the graft busters would focus on Nurhadi’s bribery case first.

Critics have lambasted the decision, saying it contrasted with the antigraft body’s decision to open investigations into alleged obstruction of justice pertaining to former House of Representatives speaker Setya Novanto in the prominent e-ID corruption case.

“If the public finds out the KPK lacks the courage to investigate the figures that protected the suspects, the KPK will lose credibility as a law enforcement institution,” said Bambang.

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Responding to the criticism, KPK acting spokesperson Ali Fikri said the antigraft body’s investigation had followed the relevant regulations and was not influenced by “another party’s requests”.

“Our work in based on the facts and witness testimonies gathered during the investigation rather than on our assumptions or feelings,” said Ali, encouraging others not to form opinions based on baseless assumptions.

Activists have also urged the KPK to open an investigation into alleged money laundering by Nurhadi in relation to the bribery case, as the suspect and his wife, Tin Zuraida, have been recorded as having made an unusually high number of financial transactions and as being unusually wealthy.

According to Nurhadi’s wealth report in 2012, he owned Rp 33.4 billion in assets, ranging from land to luxury cars.

“It should be strongly suspected that such money didn’t come from his legitimate income,” said Lalola Easter of Indonesia Corruption Watch (ICW), adding that the KPK should prosecute other parties involved in the alleged money laundering.