Attorney General Bill Lockyer today will file multiple felony charges of falsifying documents against a key aide to former Gov. Gray Davis, stemming from her involvement in the state's troubled bid to buy Oracle Corp. database software, sources said.

The charges against Kari Dohn, the Democratic governor's former director of policy, will be announced at a morning press conference and come after more than 18 months of investigation.

Dohn emerged as a key figure in legislative hearings and a subsequent criminal investigation undertaken by Lockyer's office. Neither her attorney, Allen Ruby, or the attorney general's spokesman would comment on the matter Monday.

The Davis administration's no-bid, $95 million deal to license all state employees to use Oracle's database software came under intense scrutiny after the state auditor criticized it as an unnecessary and costly purchase negotiated by top state officials ill-equipped for the task. Davis fired four top appointees as details of the transaction became public, and the deal was ultimately rescinded.

Controversy over the contract escalated when lawmakers learned that Oracle's lobbyist, Ravi Mehta, delivered a $25,000 contribution from Oracle to Davis' computer adviser at the time, Arun Baheti, at a Sacramento nightspot just days after the deal was signed.

Some critics of the sale said Oracle Chairman Larry Ellison may have used his influence to persuade the Davis administration to make the purchase.

Davis has said he didn't know of the Oracle contract, never discussed it with Ellison, and was unaware for months of the $25,000 contribution from Oracle.

Lockyer's probe initially zeroed in on Dohn's calendar, which the administration submitted to the Joint Legislative Audit Committee in response to a broad request for e-mails, calendars and other records related to the software deal.

Last year, The Bee reported that a grand jury had begun focusing on obstruction-of-justice charges, in part because Dohn's calendar was turned over after references to Ellison were omitted.

That calendar, for May 22, 2001, listed two meetings relating to the deal, one with Mehta and another with representatives of Logicon Inc., a company that brokered the agreement, which was consummated nine days later.

Investigators believed a reference to Ellison was omitted from the calendar turned over to the committee.

Two months after The Bee's article on the grand jury probe, Lockyer said the inquiry was stymied because the report let key witnesses "cover their tracks."

Sources declined to detail the circumstances surrounding the charges to be filed today against Dohn.

At the legislative hearings, Dohn testified that she knew very little about the deal and heard a pitch "in concept" about it from Mehta. She also said Mehta had told her that Ellison might call Davis about the deal, but she said she didn't think the call was ever made.

And she testified that she never mentioned the deal to Davis, despite an e-mail from a Department of Finance official suggesting she would brief Davis about it.

Testimony at the hearings also disclosed that Ellison was asked by Oracle underlings to contact Dohn and two other members of the Davis administration to thank them for "the hard work put in" after the software deal was finished.