Chile's Supreme Court has decided that former military ruler Gen Augusto Pinochet can be prosecuted on charges of misusing public funds.
Upholding a lower court ruling, the judges accepted a request for Gen Pinochet's immunity to be lifted.
Prosecutors say their inquiry relates to millions of dollars he stored in foreign bank accounts.
Gen Pinochet's lawyers say his fortune has been acquired legally, through savings, donations and interest.
It is still not clear whether he will ever take the stand in a court room and all investigators can do is ensure all the legal obstacles to a trial are removed, BBC South America correspondent Daniel Schweimler reports.
But even if Augusto Pinochet never comes to trial, his opponents are determined to ensure that the truth will come out and he will not spend his retirement in peace, our correspondent says.
Gen Pinochet, 90, has avoided trial over human rights abuses because of his health problems.
The man who ruled Chile from 1973 to 1990 after coming to power in a military coup faces a number of inquiries, including tax evasion and falsifying records.
A US investigation in 2004 discovered he had up to $27m (£15.5) in secret offshore accounts.
He now lives in a house in the mountains outside the Chilean capital, Santiago, and is rarely seen in public.
His family says he is too ill to stand trial - a claim disputed by many investigators in Chile.
According to an official inquiry, more than 3,000 people died in political violence during his rule.