[2] He is related to Estanislao Fernandez, his paternal grandfather's first cousin who served as a lawmaker from Laguna, senator, and Supreme Court associate justice.

[6] Dan Fernandez entered show business when he accepted an offer to become an actor in 1986, while he was working out at YMCA of Manila during his law school days.

He was known for acting in Mara Clara: The Movie (1996), Balawis (1996), Cobra (1997), Boy Tapang (1999), Upak Gang (2015), and Honor Thy Father (2015).

On November 20, 2009, his election was annulled by the House of Representatives Electoral Tribunal for failing to complete the two-year residency requirement prior to filing his 2007 candidacy but it was reversed by the Supreme Court on January 4, 2010.

His vote of denial to his former home network's hopes of renewing its legislative franchise sparked controversy from both the entertainment industry and the social media, branding him as a "traitor".

In the 19th Congress, he was named as the chairman of the House Committee on Public Order and Safety, making him a concurrent member of the National Security Council.

[15] He also chaired the Quad Committee, alongside Benny Abante (Manila–6th), which investigates the alleged extrajudicial killings during the drug war under former President Rodrigo Duterte, until both resigned as chairmen in November 2024 after former Mandaluyong City Police Chief Hector Grijaldo accused them of pressuring him to admit the existence of the drug war reward system.

Global Aero Bleu Corporation, partially (10%) owned by Fernandez, was accused of failing to settle a debt by Fly Noor, which filed a US$751,536.84 claim against it on November 5, 2023 regarding aircraft lease.