A statement from the Virginia State Bar described the scam, and the precautions being recommended by the FBI.

Fake cheques

In one version of the fraud, lawyers are being targeted in fictitious collection cases, where they are delivered a fake cheque. The cheque is not normally revealed to be fake until after the lawyer has transferred funds to the creditor who has supposedly procured their services.
Another variation sees lawyers receive an e-mail -- often from a verifiable out-of-state lawyer or company -- asking for assistance in collecting a debt within their state. Once they have collected the debt -- again usually from a convincing company -- they are to transfer funds, minus fees, to an offshore bank account. It is usually after this that the cheque is revealed to be a fake.

No bank liability

Successful attempts see lawyers cheated out of an amount of up to $450,000, for which their bank refuses to claim liability. Insurance companies may also fail to cover the loss.
The FBI has recommended a series of measures, including carefully verifying the identities of clients, and agreeing contractually to hold collected funds for a given amount of time before transferring them to the client.