[4] Libanan's lineage traces back to the Philippine Revolution; he is the great-grandson of Katipunero Valentín Díaz through his great-grandmother, Basilia Diaz.

[7] During the 1995 Philippine general election, Libanan ran as a congressman for Eastern Samar's at-large congressional district, eventually losing to Jose Tan Ramirez.

[8] In 1998, he was the Congressman for Eastern Samar's at-large congressional district for three terms, varying with the parties Laban ng Makabayang Masang Pilipino (LAMMP), Lakas-CMD,[9] and the Nationalist People's Coalition (NPC).

During his tenure as Congressman, he was awarded a standing ovation from the Public Attorney's Office of the Philippines after signing a law giving special allowance to PAO officials.

[15] Libanan implemented a law which requires tourist workers from the Philippines to sign a waiver removing them from any type of blame from their destination country.

[21] On the other hand, Libanan strictly opposed the tenure of Rodrigo Duterte and Ronald dela Rosa, criticizing their actions.

[6] Libanan also opposed Sara Duterte after skipping a debate on the planned P2.037 billion Office of the Vice President budget.

[27] Locally, Libanan created a task force to protect the island of Homonhon, where Ferdinand Magellan first landed in the Philippines.

"[32] A total of 58 delegates visited Martin Romualdez's house to request the administration to support the Libanan-Evardone team up.

[40][41] The graft offense was found after they allegedly bought 2,164 bags of fertilizer worth P3.25 million from Akame Marketing International in 2004.

Elda ran for the Eastern Samar lone district seat in the 2007 Philippine general election as a Lakas-CMD party candidate but did not win.