Two former employees of an Edison law firm admitted Monday to embezzling more than $788,000 during a two-and-a-half-year period.

From February 2005 to September 2007, they wrote checks on the firm’s trust and business accounts to themselves and to their creditors and hid the theft by altering the payee information in the firm’s accounting system, according to court documents.

Marla Deptula, 45, of Sayreville, and Rose Crabbe, 31, of Plainfield, each pleaded guilty before U.S. District Judge Peter Sheridan in Newark to one count of conspiracy to commit mail fraud.

Deptula also pleaded guilty to one count of subscribing to a false tax return.

The U.S. Attorney’s Office declined to identify the firm in accordance with a protocol established in a previous embezzlement case, says spokesman Matthew Reilly.

Deptula, a secretary in the firm’s real estate department, had access to the firm’s bank accounts and received the vast majority of the stolen funds, authorities claim. They did not identify Crabbe’s position except to say she was an administrative employee.

The defendants used the law firm’s money to pay credit card bills, property taxes and child-care expenses, and made out checks to themselves, according to court papers.

To support the mail fraud charges, authorities cite law firm checks the defendants mailed to credit card companies, amounting to $6,700 for Deptula and $1,300 for Crabbe. The complaint also cites two checks, totaling more than $3,000, drawn on the law firm’s attorney trust account, which Deptula allegedly deposited in her own account.

Deptula was also accused of filing a 2007 tax return listing income of $72,000 but omitting $275,000 she received from the fraud scheme that year.

The conspiracy count to which both defendants pleaded guilty carries a maximum potential penalty of 20 years in prison and a $250,000 fine, or twice the gross gain or loss from the offense.

The tax count to which Deptula pleaded guilty carries a maximum potential penalty of three years in prison and a $250,000 fine or twice the gross gain or loss from the offense.

Deptula is now a paralegal at Stathis & Leonardis in Edison, according to her profile on the website LinkedIn. Partners at that firm did not reply to a reporter’s messages.

From 1995 to 1998, she worked for Howard Bloom, who had a solo practice in Union. Bloom, now with Javerbaum, Wurgaft, Hicks, Kahn, Wikstrom & Sinins in Springfield, says he was surprised to learn Deptula was charged with embezzlement. He calls her “one of the better real estate secretaries I had.”

Bloom says Deptula left his firm for Gill & Chamas in Woodbridge. Peter Chamas says he recalls Deptula working as a legal secretary for his firm about 10 years ago but did not remember where she went afterward. He says her tenure at the firm was uneventful.

Deptula is represented by Assistant Federal Public Defender Andrea Bergman, who declines to discuss the case other than to say Stathis & Leonardis is not the victim.

Deptula could not be reached for comment. When a reporter called Stathis & Leonardis and asked for Deptula, a woman who answered the phone said she could not take the call and hung up.

Crabbe is represented by Michael Armstrong, head of a Willingboro firm, who did not return a call. Crabbe hung up on a reporter when reached on her cell phone.

Sentencing is scheduled for Feb. 25, 2013. •