Complicated yarn, this business involving Washington, D.C. Metropolitan Police Department Capt. Melvin Gresham. One easy lawyering lesson, though: file your paperwork on time.

Capt. Gresham has been the subject of news stories concerning his alleged accident with a D.C. Metro bus, and later his lawsuit claiming a Drug Enforcement Administration raid on a birthday party was retaliation for his whistleblowing activities. The veteran police officer sued, demanding $100 million and making many allegations of corrupt activities within the D.C. department.

Here's the lawyering lesson, as conveyed this week in a decision by U.S. District Judge Richardo Urbina.

The District of Columbia asked the judge on July 22, 2009 to dismiss all the claims. This was a standard maneuver, for which a standard response was expected. Gresham and his attorneys, though, failed to file a timely response. Well past the deadline, in October, Gresham's attorneys got around to filing documents.

Too late. As Judge Urbina noted:

"It is well settled that a plaintiff’s failure to respond to a motion to dismiss permits a court to grant the motion as conceded...(and) The plaintiffs have not offered any excuse for their failure to respond in a timely fashion, nor have they moved for leave to late-file an opposition."

Case dismissed.