PARIS (AP) - A lawyer for Mr Nicolas Sarkozy slammed an investigation into the campaign finances of the former French president, saying he is being treated "scandalously".

Lawyer Thierry Herzog says on Friday, March 22, that Mr Sarkozy remains "combative" but still considers that he "has been treated scandalously".

Mr Herzog's comments on French radio RTL come a day after a judge filed preliminary charges against Mr Sarkozy, formally placing him under investigation over allegations that he illegally took donations from France's richest woman on the way to his 2007 election victory.

Mr Sarkozy is charged with "abuse of someone in an impaired state" in the case involving L'Oreal cosmetics heiress Liliane Bettencourt, who is now 90.

The charges carry a maximum penalty of 3 years imprisonment and a fine of 375,000 euros (S$605,800).