[10] AMIN achieved the minimum threshold despite election irregularities that nullified some of its votes,[11] but the Supreme Court then issued a temporary restraining order that prevented the party-list representatives from being sworn in.

After a two-year delay, the Supreme Court in July 2003 lifted the order and he was finally installed as a representative from Basilan at age 30.

[13] Being a human rights advocate, Hataman opposed Gov, Akabar's implementation of indiscriminate warrantless arrests in Basilan.

Captured suspect and former Tuburan town mayor Hajuron Jamiri accused both Mujiv and his brother Jim as being the masterminds of the November 2007 bombing at the House of Representatives that killed four people including Wahab Akbar.

Jamiri claimed in a two-page affidavit that Mujiv and Jim wanted Akbar dead because Basilan would "not be at peace" under his administration.

[16] On December 22, 2011, due to the "Reform Programs" of President Benigno Aquino III Congressman Hataman was appointed as Officer-In-Charge of the Autonomous Region in Muslim Mindanao.

But months before the filing of candidacy for 2013 election he was convinced by many cause oriented groups in Mindanao to pursue for a new mandate.

As per law, Hataman as Regional Governor of the ARMM at the time of the region's abolishment automatically becomes a member of the BTA but opted against joining the interim body so he could focus on pursuing local humanitarian and security programs in his home province of Basilan.

[20] Mujiv served as a program coordinator of the Kahapan Foundation—Moro Human Rights Center (Kahapan-MHRC).

[1]: 70  When he was elected to Congress, he sponsored the Anti-Discrimination Bill, which affirmed the International Convention against All form of Racial Discrimination.

In a 2004 Philippine Daily Inquirer report, Mujiv was cited as one of the "poorest" congressmen serving in the House of Representatives, with a net worth of only P420,000.

[22] According to a BusinessWorld article, Hataman in 2004 started a company with his brother that distributes fresh fish from Mindanao to businesses in Manila.