The story of those forged letters to lawmakers sent by a Washington lobby firm has taken another interesting turn.

Bonner and Associates, the firm that sent the letters on behalf of a coal industry client, is now trying to imply that the employee responsible deliberately engineered the episode to discredit Bonner -- but is offering no evidence to support that notion.

In a letter to Rep. Ed Markey, who is probing the incident, Steven Ross, a lawyer for Bonner, wrote that the firm was "the victim of a fraud," and that the staffer who sent the letters had joined Bonner the previous week "with the pre-determined intent of engaging in fraudulent activity." Ross wrote that Bonner had referred the matter to law enforcement.

The forged letters went to at least three Democratic lawmakers, purporting to come from local community and minority groups, and urging them to vote against the climate change bill that recently passed the House. They were sent on behalf of the American Coalition for Clean Coal Electricity, a coal industry group that opposes the bill. Markey had previously asked Bonner for answers to several detailed questions about the incident. The letter from Ross, who works for Akin Gump, was viewed by the Wall Street Journal (sub. req.).

But let's look closely at Ross's letter. Its clear implication is that the employee who sent the forged letters was a political opponent of Bonner or its client, and was deliberately trying to set Bonner up.

But Ross doesn't explicitly come out and state that, presumably because he lacks the evidence to do so. And the fact that the employee had a "pre-determined intent" to send fraudulent letters tells us little about his or her motivation. Indeed, Ross admits that Bonner does not know "the complete motivation" of the employee.

Ross adds:

B&A looks forward to constantly improving its internal systems and will assist your Committee and the U.S. Attorney for the District of Columbia in its investigation into this matter to the fullest extent possible...

But that carefully avoids saying that the U.S. attorney's office -- which declined to comment to the Journal -- has actually opened any criminal investigation. (Of course, there have already been calls for Bonner itself to be investigated for mail fraud in connection with the letters.)

And Ross, of course, wouldn't elaborate to the Journal.

Ross's letter to Markey, then, appears to be a carefully worded effort to portray Bonner as a victim rather than a perpetrator, but without offering any hard evidence to support that claim.

Ross also writes that "it is difficult to defend against a person bent on committing fraud." But that ignores the evidence that, as we've reported, Bonner's business methods -- in which it uses poorly-trained and low-paid temporary employees to generate "grassroots" support for corporate clients' campaigns, and fires those who under-perform -- makes such fraud all but inevitable.