Marcelo explained that his being a presidential appointee like Perez was not enough reason for him to stay off the case.
The Ombudsman recalled that when he was still solicitor general, some case decisions contradicted the position of the Department of Justice (DOJ).
"We observe the independence of agencies that are co-equal bodies," Marcelo stressed.
He also said the Office of the Ombudsman will observe utmost independence in handling high-profile cases.
Jimenez filed on Monday charges of plunder, extortion, obstruction of justice, violation of the Code of Ethical Standards for Government Officials and Employees, and graft and corruption against Perez.
Cited as co-respondents in the plunder case were Perez’s brother-in-law Ramon Arceo Jr., businessman Ernest Escaler and some John Does.
Jimenez alleged that Perez demanded $2 million from him in exchange for deliberately delaying the extradition proceedings initiated by the United States government against the legislator.
Jimenez said the money was taken from his account at the Trade and Commerce Bank in Uruguay, coursed through a branch of the same bank Cayman Islands, then through the Chase Manhattan Bank in New York and finally to an account held by Escaler at the Coutts Bank in Hong Kong.
Arceo was implicated in the case for allegedly receiving a portion of the $2 million.
Marcelo said the cases against Perez will undergo the normal process, but would apply the "high confidentiality rule."
In another development, Marcelo vowed to complete all the cases, including the high-profile ones, pending before his office by the first quarter of 2003.
Among them was the perjury complaint leveled by the National Bureau of Investigation (NBI) against Sen. Panfilo Lacson arising from the senator’s alleged failure to reflect in his Statement of Assets and Liabilities for 1997 to 2001 his dollar accounts in the US.
Another case was the complaint filed by former Public Estates Authority official Sulficio Tagud Jr. against 16 officials of the agency and a private contractor in connection with the alleged P600-million mess pertaining the construction of the President Diosdado Macapagal Boulevard on the reclamation site in Pasay City.
Marcelo said some of the cases were still in the preliminary investigation stage.
PlunderWatch led by militant priest Fr. Joe Dizon has also initiated a plunder charge against Presidential Legal Counsel Avelino Cruz who, like Marcelo, belonged to the Villaraza Law office.
Dizon urged Marcelo to inhibit himself from the investigation of the case, but the Ombudsman said he has not made any decision yet.
"I will cross the bridge when I get there, The case is not yet with me," Marcelo said.