Breaking up, as they say, is hard to do, especially at law firms, where splits involve money, clients and egos.

Washington lawyer Edward H. Forgotson and his former partners, Christopher R. (Kip) O'Neill -- son of House Speaker Thomas P. (Tip) O'Neill Jr. -- and Barry L. Haase, recently settled a stormy dispute that began more than a year ago when Forgotson announced he was leaving to join the Washington office of the New York firm Shea & Gould.

According to O'Neill, Forgotson told him his new salary was to be "in the vicinity of $500,000 a year."

When a news reporter last year asked the lawyers representing the lawyers on both sides for a copy of the court papers, they turned around and asked D.C. Superior Court Judge Paul F. McArdle to seal the file -- which he obligingly did.

After the settlement was reached last week, however, McArdle opened the file, revealing evidence of what appeared to be a nasty split.

Forgotson -- who said he had brought in 65 to 80 percent of the O'Neill firm's fees for 2 1/2 years -- claimed in a $1.5 million lawsuit that O'Neill and Haase kicked him and a few loyalists out of their offices, changed the locks on the doors, refused to give him his client files and bounced his last paycheck.

The court papers indicate the dispute centered on a huge Texas energy client, Texas Oil and Gas Corp. (TXO), which the O'Neill firm and Shea & Gould had shared.

Forgotson said in his court papers that Haase told him he would inflict physical damage (which cannot be described in a family newspaper) if Forgotson did not tell people that the reason he was going to Shea & Gould was that TXO wanted to consolidate all its work in one firm.

Forgotson also said in a sworn statement that Haase further told him O'Neill "would ruin me in Washington," if Forgotson gave any other explanation for his departure.

O'Neill -- who says he had heard reports that Forgotson was "maligning my professional ability" -- said in court papers that Forgotson's account of his departure is "clearly mistaken and incorrect" on several points.

Tempers have since cooled. Haase declined comment last week except to say that the dispute was all over and that the firm is doing fine.

As for O'Neill, he predicted in his affidavit a year ago that despite Forgotson's departure, the firm's billings for the upcoming 12 months would exceed $1.5 to $2 million.

As for Texas Oil and Gas, it is among 12 clients listed as "inactive" in lobbying reports filed by O'Neill & Haase with the clerk of the House.