Serial protester Castislav 'Sam' Bracanov has been charged over an incident in which mud was thrown over Act MP John Banks.
Bracanov, 78, appeared in Auckland District Court yesterday afternoon charged with common assault over the incident.
He was remanded on bail until June.
Banks was walking into the High Court at Auckland on Monday when a bucket of mud was thrown at him, hitting him on the face and arm.
The start of his trial, on a charge of knowingly filing a false election return, was delayed by 90 minutes while he returned home and changed his suit.
Bracanov is known for high profile protests, having previously been arrested for plotting to throw horse manure at Prince Charles and wife Camilla in 2012.
He was also arrested in 1994 for spraying air freshener at Prince Charles.