Former MP Taito Phillip Field says he was not clear what the law surrounding helping overstayers was, despite helping large numbers with immigration issues in his electorate office.
Mr Field, who later became an independent MP, denies 35 charges of bribery, corruption and wrongdoing relating to claims that he gave immigration assistance in return for work on his properties.
On Tuesday he completed almost four days of giving evidence.
The Crown then began its cross-examination, with prosecutor David Johnstone focusing on Mr Field's understanding of bribes and the law surrounding overstayers.
Mr Field said he did not see it as illegal when he helped overstayers who came to his office.
He said like all MPs his electorate office was there to help people unconditionally and free of charge.
Mr Field said if he reported all the overstayers who sought his help few people would have come to his office.
Earlier Mr Field told the court he took some foolish actions, but his family was under enormous pressure and he was fighting for his political career.
Mr Field denied deliberately obstructing the Ingram Inquiry in 2005 into the accusations, or perverting the course of justice.
He said he had no intention of misleading the inquiry and gave answers to the best of his ability, relying on his memory, at the time.
Mr Johnstone's cross-examination is expected to take about two days.