The lawyer who filed the impeachment complaint against Chief Justice Maria Lourdes Sereno on Thursday said the chief magistrate should just resign and spare herself the attacks during an impeachment trial.

"If I were Chief Justice Sereno, I will just resign to avoid the humiliation and all the inconvenience of this impeachment trial. I have very strong grounds and documents to prove my allegations. She better think it over. You cannot [stop] the members of Congress from asking questions, questions that may even be off-tangent just to attack her. They will really tear you apart," Atty. Lorenzo Gadon told ANC's Early Edition.

In the interview, Gadon denied that former Senator and defeated vice-presidential candidate Ferdinand "Bongbong" Marcos Jr. or President Rodrigo Duterte is behind the complaint.

• Bongbong, Duterte backing Sereno impeachment? Lawyer says no

He also claimed he has the numbers to impeach Sereno, both in the House of Representatives and Senate.

"There are only 5 or 6 yellow senators there. So you can guess. Take a guess. Not only that, when some people are trying to file a case against Vice President Leni Robredo, President Duterte himself told congressmen: 'Stop it.' In my case, Malacanang has said they will not meddle in this issue," he said.

• READ: Gadon's impeachment complaint vs Sereno

Gadon said the strongest ground to impeach Sereno is her failure to declare in her statement of assets, liabilities and net worth (SALN) millions of pesos in fees paid to her as a lawyer in the Piatco case.

Another accusation leveled by Gadon is the Chief Justice's purchase of a P5.1 million Land Cruiser 2017 model, which the lawyer deems as extravagant.

"She has already been issued a Starex and a Camry. She also bought 2 big motorcycles for her escorts," he said.

Asked why the purchase of a vehicle is considered "extravagant" for the highest magistrate in the land, he said: "You have to consider that President Duterte himself, the highest official in the land, did not buy a new vehicle. When he's in Davao he is just using a multicab and in Manila he is using the old car used by President Gloria Macapagal Arroyo."

The lawyer accused Sereno of embellishing her personal data sheets, saying this is a high crime.

He also claimed at least 3 Supreme Court magistrates are willing to testify in the impeachment trial if summoned by lawmakers. He said the magistrates want to "save the judiciary."

The House justice panel earlier voted Gadon's impeachment complaint against Sereno sufficient in form and substance.

However, Sereno impeachment spokesman Atty. Carlo Cruz said many of the allegations in the Gadon complaint are unsupported by evidence or rely mainly on hearsay consisting of newspaper clippings."

Atty. Carlo Cruz, spokesperson of CJ Sereno, reacts to the results of the House voting on the two impeachment complaints vs Sereno #ANCRecap pic.twitter.com/JAdDIjaKgm

— ABS-CBN News Channel (@ANCALERTS) September 13, 2017

"None of the allegations rises to an impeachable offense. The complaint against her seems designed to maximize the political spectacle, with the goal of eroding her credibility through innuendo and malicious allegations," said Cruz, a veteran lawyer just named as Sereno's impeachment spokesperson.

"This is detrimental to the independence of the judiciary upon whom all citizens rely to defend their rights and to check any abuse," he added.