The prosecution will ask the Senate impeachment court to declare Davao City Mayor Sebastian “Baste” Duterte a hostile witness when he takes the stand in the impeachment trial of Vice President Sara Duterte, private prosecutor Atty. Benjamin “Jay” Tolosa Jr. said on Saturday.

In a Saturday News Forum, Tolosa Jr. said the panel will seek the declaration as it questions the mayor about possible transactions between the Davao City government and companies linked to the Vice President.

“We will ask the court to declare him as a hostile witness,” Tolosa said.

The mayor is scheduled to testify before the impeachment court on September 23 as part of the prosecution’s presentation under Article II, which concerns allegations of unexplained wealth and the Vice President’s declared business interests.

Tolosa said the mayor would be asked to testify in connection with GenCorp Industries Inc., one of the companies listed in Sara's Statement of Assets, Liabilities and Net Worth (SALN) in which she has declared business interests.

“Pinapatawag po natin siya dahil main reason diyan dahil siya ang mayor no ng City of Davao at nakita natin doon sa SALN ng bise presidente meron mga iba-ibang kumpanya 'no na nakadeklara doon na kung saan siya mayroong financial interest so kasama diyan 'yung kumpanyang Gen Corp Industries. Gusto nating makita um kung nagkaroon ba ng any dealings itong kumpanya na to with the city government of Davao,“ Tolosa said.

Tolosa explained that a witness may be declared hostile if the prosecution can demonstrate that the witness’ interests are adverse to those of the party calling them.

“Katulad ng other witness, pare-pareho naman ’yung pamantayan diyan. If you’ll be able to show that yung interes of the witness [is] adverse to the party calling him, in this case yung prosecution, then mako-qualify siya as a hostile witness,” he said.

If declared hostile, the prosecution would be allowed to ask leading questions, subject to the impeachment court’s rules.

The impeachment court issued the subpoena for Baste Duterte on September 16. His office confirmed receiving the subpoena on September 18.

He is tentatively scheduled to appear before the impeachment court on Sept. 23, although the court may still adjust the date of his appearance depending on the progress of the testimonies of earlier witnesses.