Salim Mehajer's stint outside Silverwater prison may be short-lived after he was convicted of multiple counts of electoral fraud.

Salim Mehajer arrives at Sydney's Central Local Court on Wednesday morning. Credit:AAP

Local Court magistrate Beverley Schurr found on Wednesday the property developer and former Auburn deputy mayor engaged in a "joint criminal enterprise" with his sister Fatima to rig the September 2012 local government election, which catapulted him into public office.

Ms Schurr said the pair exchanged "numerous" incriminating text messages on July 30, 2012, shortly before the close of the electoral roll.

In a statement after the decision, Mehajer said he had "huge confidence in the justice system and I am sure everything will be okay".