OAKLAND -- A 42-year-old San Lorenzo woman pleaded guilty Tuesday to mail fraud and tax evasion charges after embezzling more than $300,000 from the clients of a Union City law firm while working as a paralegal, authorities said.

Ana Lissa Reyes, also known as Lizzette Reyes, began working at the Law Offices of Brian Ching in 1994. According to a court complaint, Reyes was fired in the same year after her cousin and Ching's wife, Gloria Custodio, discovered she'd stolen $10,000 from a client trust account but that incident was not part of the criminal complaint.

A month later, she was rehired on the condition that she attend counseling to rectify the behavior and work extra hours to compensate for what she stole, according to United States Attorney Melinda Haag.

By 2006, Ching and Custodio began exercising less oversight over Reyes as their son's health deteriorated, culminating in his death in 2011.

From 2006 to 2011, Reyes embezzled a total of $327,795.05 from Ching's firm and from his clients, Haag said. She also underreported her income for each of these years and admitted that she owed a significant amount of money to the IRS.

Reyes was eventually fired in June of that year, as the couple responded to their clients' complaints that they had not received their settlement checks despite their insurance companies' assertion that the checks had been cashed.

She admitted that while working as a paralegal, secretary and office manager for the firm, she settled various claims without informing the firm or its clients and pocketed the settlement proceeds, Haag said. She also admitted to engaging clients without the law firm's knowledge and to stealing their retainer fees.

According to Haag, Reyes created a bogus company, Lincoln Litigation, as part of her scheme and would correspond with clients without Ching's knowledge and fool them into thinking their cases were ongoing. She registered the business to an address in Oakland, saying that she wanted to provide her own legal services while still working as Ching's office manager.

Reyes was charged with five counts of mail fraud and six counts of tax evasion on January 25 and is currently out of custody on a $100,000 bond. Her sentencing is scheduled for October 10 at 2 p.m. at the U.S. District Court in Oakland.

The maximum penalty for each count of mail fraud is 20 years in prison and a fine of $250,000, and the maximum penalty for each count of tax evasion is six years in prison and a fine of $250,000. She will also be required to pay restitution on both counts.

Contact Erin Ivie at eivie@bayareanewsgroup.com. Follow her at Twitter.com/erin_ivie.