By Dena Aubin and Karen Freifeld
NEW YORK (Reuters) - New York Attorney General Eric Schneiderman faces an uphill climb in building a case against Exxon Mobil Corp for not writing down assets amid the oil-price slump because of the broad leeway that energy companies have enjoyed reporting under U.S. rules, accounting experts said.
Schneiderman is investigating Exxon's accounting practices and why the oil giant has not taken writedowns even while oil prices have fallen, a person familiar with the matter told Reuters.
The price drop of more than 60 percent since 2014 has forced many integrated oil producers around the world to write down the value of their wells, leases and equipment, and Exxon is the only major producer to hold off so far. Oil in many wells can no longer be profitably recovered, and failing to write them down could give a misleading picture of a company's financial health.
But accounting experts said it was far from clear that Exxon's lack of writedowns signaled any wrongdoing. Accounting rules give companies a choice of methods for valuing and impairing their assets, and writedowns can vary sharply based on the method used and other factors, they said.
"This is an extremely subjective area," said Tom Selling, author of The Accounting Onion blog. "Everyone will have a different pattern of writedowns depending on how old their fields are and how much they cost to develop."
Doug Cohen, spokesman for the AG's office, declined comment.
An Exxon spokesman on Friday told Reuters its accounting follows rules of the U.S. Securities and Exchange Commission and the Financial Accounting Standards Board, which sets reporting standards for U.S. public companies.
The largest U.S. oil companies have historically not taken large charges to write down the value of their assets when commodity prices tumble, said Brian Youngberg, oil company analyst at Edward Jones in St. Louis.
Companies are reluctant to take writedowns because they reduce income and assets on the balance sheet, and once assets are written down, they cannot be written up, said Larry Crumbley, accounting professor emeritus at Louisiana State University.
Accounting rules do not require companies to take impairments for a temporary drop in oil prices, but the rules do not define the timeframe of a temporary slump, said Terry Crain, accounting professor emeritus at the University of Oklahoma.
"Is it a month or two, or several years?" Crain said. "It falls in a gray area."
Chevron Corp, which took $2.8 billion of impairments and other charges in the second quarter, may not look at the current slump as temporary, Crain said.
But Robert McTamaney, a lawyer with Carter, Ledyard & Milburn, said if companies believe prices will soon rise again, taking an impairment is the wrong move. He also noted that Exxon, as one of the nation's oldest oil producers, may be already carrying many of its rigs and other equipment at much lower prices, making writedowns unnecessary.
"From glancing at it, I think Exxon has substantial arguments that their accounting is correct," he said.
New York attorneys generals have a powerful tool for fighting accounting misconduct with the Martin Act, the state's securities fraud statute. The act allows for both civil and criminal charges, and the attorney general does not have to prove an intent to deceive.
Exxon is not the first company whose accounting has come under the scrutiny of the New York attorney general's office. Former American International Group chief executive officer Maurice "Hank" Greenberg went on trial in New York state court Sept. 13, in a case stemming from a probe of AIG's accounting practices.
McTamaney, who has been critical of the use of the Martin Act by New York attorneys general over the last decade or so, said he wondered why Schneiderman is bringing a case that "if it belongs anywhere, should be with the SEC."
The SEC in 2013 questioned why Exxon had not taken an impairment charge despite stating it was making "no money" on U.S. natural gas due to falling prices, according to a letter published on the commission's website. The SEC declined comment on Friday on whether it is still looking into Exxon's accounting.
(Reporting By Dena Aubin and Karen Freifeld; Additional reporting by Anna Driver; Editing by Anthony Lin and Bernard Orr)