A senior official from the Construction, Forestry, Mining and Energy Union has appeared in the Perth Magistrates court to face a charge of trespass.

It is alleged the assistant secretary of the union, Joe McDonald, entered the Lakeside Shopping Centre building site at Joondalup in February and refused to leave when asked by site official.

The court has heard Mr McDonald had his state and federal tickets to enter building sites revoked in July last year.

Today his lawyer argued Mr McDonald was on the site lawfully and left within a reasonable time after he was requested to do so.

The Magistrate, Joe Randazzo, reserved his judgement until Thursday so he could consider relevant case law.