WASHINGTON — When state Democrats unveiled their proposed congressional districts in 2011, one of the central justifications for the squirrely lines in Western Maryland was a need to “maintain” the Interstate 270 corridor.

The decision to lump Republican Western Maryland in with Democratic portions of Montgomery and Frederick counties in the 6th Congressional District wasn’t about diluting GOP influence, the argument went: It was about keeping the growth-heavy biotech region of the state within one district.

The chair of the state’s redistricting commission, Jeanne D. Hitchcock, made that case to The Baltimore Sun at the time.

But depositions and emails released Wednesday in a federal lawsuit challenging the constitutionality of the boundaries have raised questions about the argument.

One problem: The map does not, in fact, keep the corridor intact. The interstate begins not in the 6th District, represented by Democratic Rep. John Delaney, but in the 8th Congressional District, represented by Democratic Rep. Jamie Raskin. The 8th District, not the 6th, is also home to the Bethesda-based National Institutes of Health, the anchor of the state’s burgeoning biotech corridor. The interstate connects the Capital Beltway in Montgomery County to Frederick.

The depositions show that none of the top officials involved in the redistricting six years ago could recall reviewing data about the corridor’s commuting patterns, economy or projected growth. Hitchcock, a longtime Martin O’Malley confidant and the chair of the Governor’s Redistricting Advisory Committee, said she “would not have asked” for data about the corridor.

Hitchcock, who told attorneys that she viewed her role on the commission as facilitating public hearings on the maps, declined to comment.

Senate President Thomas V. Mike Miller, also a member of the commission, said he didn’t recall reviewing data on the corridor.

Whatever the motivation, the result was unambiguous: Adding more Democratic voters helped Delaney oust longtime Republican Rep. Roscoe G. Bartlett in the 2012 election. Delaney had no part in crafting the map. His own home was drawn outside his district.

It wasn’t just outsiders skeptical of the I-270 argument. Jason Gleason, chief of staff to Rep. John Sarbanes of Baltimore County, sent an email during a briefing by the redistricting commission, according to the motion filed in the litigation.

“I’m not sure I buy the themes they are selling,” Gleason wrote. “Hopefully they have some better ones for the public face of it.”

Gleason, through a spokesman, did not respond to a request for comment.

—?John Fritze