Lieu made a name for himself by taking to Twitter to challenge the actions and the tweets of President Donald Trump.
The Torrance Democrat calls the president a cyber bully and has garnered 350,000 followers since he began taking on President Trump on the Commander in Chief's preferred forum.
He minced no words, sometimes using profane language.
One typical tweet followed the incident when Secretary of State Rex Tillerson supposedly called the president a moron.
President Trump tweeted that it was fake news, to which Lieu tweeted: "What makes America great is that government doesn't control the free press. Even morons should know that."
Lieu, a former state lawmaker, was in Sacramento for a voters forum, at which he criticized the president with being reckless for conducting foreign policy on Twitter with his tweets about North Korea.