The Securities and Exchange Commission yesterday accused Cincinnati-based Baldwin-United Corp. of engaging in misleading accounting practices before the company's financial collapse in September 1983.

The SEC charges were contained in three consent decrees in which the corporation and several of its former officers agreed to injunctions against future fraudulent actions of the type alleged by the SEC.

The agreements were made without admission or denial of guilt.

However, in a related matter, Baldwin-United and its subsidiary holding company, D. H. Baldwin Co., filed a $1.3 billion lawsuit against Merrill Lynch & Co. of New York and its subsidiary, Merrill Lynch, Pierce, Fenner & Smith Inc.

The suit, filed in U.S. District Court in Cincinnati, claims Merrill Lynch provided false and inexpert advice in Baldwin's 1982 acquisition of MGIC Investment Corp.

The $1.2 billion MGIC purchase was a diversification move designed to help Baldwin shore up its sagging financial fortunes. It failed.

Baldwin, a financial services operation, had borrowed heavily to take over MGIC. But many analysts regard the ill-fated deal as the final slip that landed Baldwin in U.S. Bankruptcy Court, seeking protection from creditors as it tried to reorganize under Chapter 11 of the bankruptcy code.

A Merrill Lynch spokesman in New York dismissed Baldwin's charges as "particularly incredible."

Much of the information used by Merrill Lynch to advise Baldwin in the MGIC matter came in writing from Baldwin itself, the Merrill Lynch spokesman said. "Merrill Lynch will defend its position in this matter vigorously and forcefully," the spokesman said.

The SEC may have provided Merrill Lynch with some ammunition.

In its consent decree with Baldwin yesterday, the SEC accused the company of making "false statements concerning the financing for two corporate acquisitions, the acquisition of Sperry & Hutchinson Co. in 1981 and the acquisition of MGIC Investment Corp. in 1982."

In the 1982 acquisition, according to the SEC, "Baldwin provided false information for inclusion in MGIC's proxy statement, which falsely stated that Baldwin had a $600 million loan commitment and could use $500 million of insurance premiums to finance the merger.

"In fact," the SEC charges continued, Baldwin "had no such commitment, nor had it received regulatory approval to use insurance premiums for the acquisition at that time."

Also, according to the SEC, Baldwin sold $100 million of debentures, using false information, in connection with the MGIC matter. In this case, Baldwin allegedly failed "to disclose the insolvency and related regulatory problems of D. H. Baldwin Co.'s primary subsidiaries."

The SEC also accused Baldwin of using accounting controls that were "materially deficient with regard" to its business in single-premium deferred annuities.

Named in the SEC's charges were Morley P. Thompson, former president and chief executive officer of Baldwin-United; Timothy P. Hartman, Baldwin-United's chief financial officer until April 1982; Edward D. Jones & Co., the St. Louis broker-dealer that underwrote the $100 million debenture sale; and Robert S. Harrison, who served as Baldwin-United's chief financial officer from April 1982 until April 1983.