Lawyers allied with Vice President Sara Duterte on Friday challenged the House Committee on Justice’s use of subpoenas, arguing before the Supreme Court that these were used to build evidence rather than assess existing complaints.

In a Petition-in-Intervention, the group said the subpoenas point to a “constitutional defect” in the impeachment process, claiming they allow complainants to strengthen their case after filing.

“We have specifically raised the issue of whether those proceedings and the subpoena issued pursuant to them constitute an impermissible fishing expedition designed to cure the facial infirmities of the complaints rather than examine evidence supporting adequately pleaded and already sufficient charges,” said Edizer Luntan, secretary general of the One Bangsamoro Movement.

The group argued that issuing subpoenas for evidence not originally attached to complaints undermines the requirement that impeachment cases must be backed by sufficient facts from the outset.

They asked the Supreme Court to determine whether the House committed “grave abuse of discretion.”

“The duty of the Supreme Court [is] to arrest grave abuse before a constitutionally defective process hardens into precedent,” the group said.

The intervenors also said their participation is necessary to prevent the impeachment process from being reshaped into one driven by post-filing evidence gathering.

“At stake,” they added, “is the integrity of constitutional processes… After all, the Constitution must govern impeachment, not the other way around.”