A former customer service manager at the Freeland branch of Whidbey Island Bank is facing time in federal prison for embezzling $162,000 from the bank.

Shawna Brown is scheduled to be sentenced Friday in U.S. District Court in Seattle for one count of bank embezzlement. She pleaded guilty in September as part of a plea agreement.

The U.S. Attorney is recommending a sentence of 15 months in prison, which is the maximum under the plea agreement.

The sentencing memorandum describes the “lengthy scheme” in which Brown thwarted the bank’s internal controls and created fake documents on a daily basis to avoid detection.

Brown was a “low level supervisor” who was in charge of three to six bank tellers.

Brown stole cash from her cash drawer from 2010 until she was caught in August 2013.

Brown concealed the theft by creating a “cash ticket” in the computer system without creating a corresponding ticket in the bank’s ledger; instead, she created a false “general ledger screen shot from a template on her computer,” the sentencing memorandum states.

“The defendant engaged in this deceptive conduct nearly every day for three years, including days when she had mandatory vacation,” Assistant U.S. Attorney Justin Arnold wrote.

Brown convinced her fellow employees to allow her to balance the general ledger — convincing them that she was “doing them a favor” — even though it was against bank policy, the document states.

The theft was finally discovered in August 2013 when an injury forced Brown to miss work and other employees uncovered the scheme. She admitted to the crime in interviews with the FBI and the FDIC, the report states.

“The defendant’s actions not only caused the bank economic harm, but negatively impacted the lives of the defendant’s co-workers,” Arnold wrote.

The branch manager was reprimanded and placed on probation for allowing Brown to work on vacation. Other co-workers were disciplined and the branch lost half of its staff, the document states.

The document states that Brown needed the money because of “unforeseen economic problems in her household” and that she had a troubled upbringing which caused depression.

Brown is not accused of stealing from bank customers.

“There was no involvement of customer funds or customer accounts,” said Bryan McDonald, the executive vice president of Heritage Bank.

Whidbey Island Bank and Heritage Bank merged in May.