Before entering the special court in the remote capital of Naypyitaw, lawyers said that Suu Kyi's acquittal by the five-judge panel "would be a good example that rule of law prevails in the country."
The 65-year-old Nobel Peace Prize winner has been detained for 15 of the past 21 years but was never convicted of any crime until August 2009. She was sentenced to 18 months in prison for violating her house arrest by briefly sheltering an uninvited American who swam to her home.
The trial sparked global outrage and her conviction was widely viewed as designed to keep her detained through the country's first election in two decades on Nov. 7.
Suu Kyi has already lost two appeals and lawyers are exercising their final legal option with the Special Appellate Bench.
"We are optimistic that Daw Aung San Suu KYi will be acquitted as she was not guilty," lawyer Nyan Win said.
He said the court does not usually give its decision the same day but he could not rule out "unexpected events" since 'Daw Suu's case is a special case."
But a quick ruling granting Suu Kyi an early release would appear unlikely, since court decisions almost invariably favour the government. Granting her freedom would appear to threaten the junta's carefully crafted plans for an orderly election by putting the spotlight on her and her now-disbanded party's boycott of the polls, which the party claims are unfair and undemocratic.
Suu Kyi's 18-month house arrest is set to expire on Nov. 13, a week after the country's election. There is widespread speculation the junta will release her after its expected win at the polls.
Suu Kyi's lawyers have argued that her house arrest was unlawful since it was based on provisions of the 1974 constitution, which was abolished after a ruling military junta seized power in 1988, said Nyan Win.
Myanmar, also known as Burma, has been under military rule since 1962. The elections of 1990 were swept by Suu Kyi's party but the military refused to relinquish power.