Jean-Claude Duvalier, former leader of Haiti, has been charged with corruption, theft and misappropriation of funds during his 15-year rule which ended in 1986.
Mr Duvalier, who denies wrongdoing, made a surprise return to Haiti two days ago after years of exile in France.
A judge will now have to decide whether the case goes to court.
Feared in his youth as the notorious dictator 'Baby Doc', Mr Duvalier cut a very different and rather forlorn figure as police escorted him away from his hotel to face interrogation over his 1971-1986 rule.
An investigating judge questioned him in court for hours and must now decide whether there is enough evidence to pursue charges, which Mr Duvalier's lawyer said were for corruption, embezzlement and criminal association.
Critics and human rights groups accuse the former leader of siphoning off hundreds of millions of dollars and of presiding over an era of brutal abuses, including extrajudicial killings and torture.
The 59-year-old was later allowed to return to the Hotel Karibe in upmarket Petionville where he has been staying since Sunday evening after returning home for the first time in 25 years.
'He is free, but has to remain at the disposal of the justice system,' his lawyer said, without saying if he could leave the country.
A French diplomatic source has said Mr Duvalier's return ticket to France is booked for tomorrow.
Mr Duvalier's unexpected return comes against the backdrop of great political uncertainty in Haiti following disputed presidential elections that spawned riots between rival factions that left five dead.
One year after a catastrophic earthquake killed 250,000 people, much of the capital Port-au-Prince remains in ruins and a cholera epidemic has claimed nearly 4,000 lives.
