Outside auditors examining a little-known Police Department account used to finance more than $178,000 in expenses under Police Commissioner Edward T. Norris are conducting the first phase of their investigation, which focuses on 50 checks selected at random.

In a letter to city officials dated Aug. 30, auditors from Ernst & Young wrote that they would inspect the 50 checks, trace deposits, examine receipts and conduct interviews with police officials. The auditors will also examine 50 randomly selected checks issued under former Police Commissioner Thomas C. Frazier.

The auditors said that phase of their probe, which began Sept. 4, would take up to two weeks and result in a report submitted to City Hall.

The auditors wrote that they would not draw conclusions in their report but added that "any obviously personal purchases noted as a result of our work will be disclosed" to city officials.

The first phase will cost between $15,000 and $25,000, the auditors wrote.

City Finance Director Peggy Watson has not received the initial report, officials said. After reviewing it, Watson will determine how or whether to proceed with a more detailed audit.

The next step might also include summaries of the types of expenses - for example, travel, meals or gifts - under Norris and a comparison with other commissioners, the auditors wrote in their letter, which was obtained by The Sun.

The auditors were hired by Mayor Martin O'Malley last month to look into the Police Department's "supplemental account," which Norris used to finance trips to New York, expensive meals at trendy restaurants and gifts for officers and others during his tenure.

Norris has said the expenses were business-related but has also apologized for his handling of the account and its lax supervision. Under Norris, many receipts contained no explanation of who attended meals or why trips were made. Norris also could not recall the reasons for several trips.

An internal police audit found about $8,400 in checks to police officials that had no receipts or other documentation to support the expenses.

Outside experts said the auditors' proposal appeared to be thorough.

Pam Markham, the supervising auditor in the City Council auditor's office of Jacksonville, Fla., said, "It's a pretty good audit plan."

Mike Taylor, president of the National Association of Local Government Auditors, agreed, saying the plan seemed solid. "It's pretty boilerplate," Taylor said.

Norris was not the first police commissioner to use the fund for travel and other expenses. The account evolved from three charities for which police officers in the 1920s and 1930s raised private funds to help officers in need and to buy athletic equipment for police leagues.