A second member of the BPD gang unit faces a charge of trying to disrupt a two-year investigation of the Academy Homes gang in Roxbury.

But unlike Det. Mel Steele, who acted out of a longstanding friendship with a member of the gang in feeding information to its members, Det. Brian Smigielski is charged with acting in a fit of pique.

Smigielski was initially the lead Boston detective in an ongoing FBI/BPD probe into the gang. But in an "information" filed in US District Court in Boston last week, the US Attorney's office charges Smigielski began feeding information about the investigation to Academy Homes members after he was taken off the case in 2009 - and ordered to hand over all his files and notes to the FBI and another BPD unit, the Special Investigations Unit.

The federal document makes two specific allegations against Smigielski:

Smigielski and Steele met with two Academy Homes members at Daisy Buchanan's on Newbury Street in January, 2010 to alert them they were under investigation. In April, 2011, the document alleges, Smigielski warned one gang member that officers could be getting ready to arrest him.

Steele pleaded guilty to a charge of lying to FBI agents when asked if he was helping out gang members. In exchange for his plea, he got a $2,000 fine and probation, but no prison time.

Court records show that Smigielski may have also reached a plea deal - a plea hearing is scheduled for a Sept. 29 before Judge Denise Casper on the charge of conspiracy to impede a federal investigation.

Last year, Smigielski received a commendation from Commissioner William Evans for his work in chasing and helping to capture two men wanted in connection with gunfire in Mattapan. The department praised him for his "courageous actions" and not retreating under danger.

Innocent, etc.