Calling himself a "battler" who knew when he was wrong, former advertising magnate William B. Tanner pleaded guilty today to one count of mail fraud and three counts of income tax evasion.

Tanner was accused of siphoning money from his former company, the William B. Tanner Co. of Memphis, and concealing the funds in fictitious accounts to avoid paying income taxes and to defraud his firm, prosecutors charged.

Assistant U.S. Attorney Dan Clancy told the court that Tanner paid kickbacks while running the advertising company and understated his taxable income by at least $100,000 a year for three years.

U.S. District Judge Robert McRae agreed to abide by a plea bargain in which Tanner would receive no more than four years in prison and a maximum fine of up to $16,000. A sentencing date was not set.

"I've been a battler, and I've won many battles when I thought I was right. In this matter, I recognized that I'm wrong, and I've prayed to the courts for mercy, but I stand ready to face the consequences," Tanner said following his appearance in federal court.

The agreement avoids the process of a grand jury indictment and federal court trial. The guilty plea was arranged with prosecutors in response to a federal information complaint filed today.

"I do not want to propose that the government would carry out the heavy burden and expense of prosecution, and I want to also avoid for my family and myself the ordeal of a long and traumatic trial," Tanner said.

He declined further comment.

"The plea agreement provides that the court may do anything from providing probation for Mr. Tanner up to the maximum incarceration of four years," said his attorney, James Neal.

Tanner, the founder and former president of William B. Tanner Co., has been the subject of a 17-month federal investigation into the allegations involving his company.

Tanner sold the firm to Media General of Richmond in 1982 for $40 million before the investigation began. After the sale, he remained Tanner Co.'s chief executive officer but resigned when the probe began.

The FBI and Internal Revenue Service raided the firm in 1983, seizing 20 boxes of company records.

Tanner Co., which specialized in selling radio and television air time, is now called Media General Broadcast Services Inc.

Tanner still faces $237 million in lawsuits from Media General, which claims he allegedly misrepresented his firm's finances when the sale was negotiated.