Zuce also claimed to have witnessed an Arroyo friend, former Lubao, Pampanga mayor Lilia Pineda, distributing bribes to the Commission on Elections (Comelec) officials gathered there.
He also challenged Pineda and the Comelec officials to undergo lie detector tests.
For almost five hours yesterday, senators grilled Zuce during the Senates inquiry into bribery allegations against Mrs. Arroyos husband, son and brother-in-law on his allegations against the President.
Zuce maintained that Mrs. Arroyo had met with several election officials at her home in La Vista subdivision in Quezon City and solicited their help in rigging the May 2004 presidential race.
Envelopes containing P30,000 in cash each were then handed out to the officials, he testified.
He said "it was impossible" for Mrs. Arroyo not to notice or know that money was being distributed.
"After the brief introductions, (Mrs. Arroyo) gave a short talk asking the (election officials) to support and help her in the coming 2004 presidential election," Zuce said.
"Shortly thereafter, (Mrs. Arroyo) bade us goodbye because she said she had another engagement. As we were leaving, Mrs. Pineda gave (election official) Johnny Icaro of Region 4 white envelopes for all of us. When we later opened them in the vehicles, we found that each envelope contained P30,000."
Mrs. Arroyos ally Sen. Miriam Defensor-Santiago questioned Zuces credibility and asked him about his background.
Under Santiagos grilling, it was learned that Zuce was a mere technical assistant in the Presidential Liaison Office for Political Affairs, then headed by political adviser Joey Rufino, and not a presidential assistant as Zuce had earlier claimed.
Apparently feeling the pressure, Zuce accepted a challenge from Sen. Alfredo Lim to undergo a lie detector test.
However, Zuce invited Mrs. Arroyo and the others implicated in his testimony to do the same. That prompted Santiago, a former Quezon City trial court judge, to inform Zuce that "a challenge to a duel is considered a crime" under the law.
Santiago also questioned Zuces motive, noting that it took him over a year to come forward with his bribery accusations. "He has many inconsistencies," she concluded.
Zuce also failed to substantiate his allegation that P12 million in alleged bribe money came from Pineda.
That prompted an irritated Sen. Lito Lapid to lecture Zuce on the subject of "hearsay" evidence. "You cannot just drag anybodys name here," he told Zuce. "We are not here to accuse but we are working in aid of legislation."
Zuces credibility also came under attack from a former Masbate mayoralty candidate Cherry Abapo, who had accused Zuce of duping him out of P1.5 million in 2001 and traded insults with Zuce at yesterdays inquiry.
Abapo said he met Zuce in June 2001 during a mayors conference in Manila where Zuce allegedly approached him and told him that he was working under Rufinos office.
They met again by chance at a parking lot outside the Comelec headquarters in Intramuros, Manila a month later. Abapo said he was following up an electoral protest he had filed.
Zuce had offered to help settle Abapos election protest for P6 million and it was agreed that Abapo would pay an initial P1.5 million, Abapo told the inquiry.
Abapo showed a deposit slip, dated March 12, 2002, showing that he had deposited P250,000 in Zuces Metrobank account at the banks United Nations street branch in Manila. This was his last payment to Zuce, he continued.
After that, Zuce disappeared after Abapo lost his electoral protest.
Abapos lawyer said Zuces admission that he received P250,000 from Abapo proved that he was an "incorrigible liar" and an "influence-peddler."
"We feel vindicated by Zuces own admission that he indeed collected money from my client. The hearing has shown Zuce (to be) an incorrigible liar who even attempted to pin us down with fantastic tales when his lack of credibility became apparent," lawyer Rodel Batocabe said in a statement issued to the media.
Malacañang officials had earlier dismissed Zuces accusations as "incredible and fantastic."
Environment Secretary Michael Defensor charged that Zuce was paid by the opposition which has been calling for Mrs. Arroyos resignation for alleged poll fraud to make false accusations and discredit the Arroyo administration.
Zuces lawyer, Liwayway Vinzons-Chato, said other witnesses will soon come forward to corroborate Zuces claims.
She contested Santiagos legal assessment of Zuces accusations, saying it was only technical. "They are just obviously trying to justify lack of merit and discredit the allegations. If they really want to disprove the statements, then produce counter evidences." With Marvin Sy, Edu Punay