The Church of Jesus Christ of Latter-day Saints is seeking to intervene in a court case that could hamper its plans for a new Church History Library on the northern border of its downtown campus.

Still distressed over parking woes associated with the LDS Church's Conference Center, which opened five years ago, a pair of Capitol Hill residents have sued trying to block the library plan. They say current plans could further hamper parking in Salt Lake City's northern neighborhoods.

The suit filed in September asks a 3rd District Court judge to stop the existing library plan because it would replace a surface parking lot and 283 parking stalls. The suit points to the Capitol Hill Master Plan, which suggests that developments that take up parking spaces need to find alternative spots for new parking.

One goal of the master plan is to "prohibit a reduction in the parking requirements for new developments in the Marmalade, Kimball and West Capitol Hill neighborhoods or in the neighborhoods where inadequate amounts of off-street parking already exist."

In this case, the church asked for and received a waiver from the city Board of Adjustment, which ruled the church has ample nearby parking for its workers and doesn't need to replace the 283 lost stalls.

The residents, Capitol Hill Community Council chairman Peter von Sivers and Bonnie Mangold, are suing Salt Lake City, asking a judge to overturn the board's decision.

"They ignored the master plan," von Sivers says of the 3 to 1 ruling last July. "The city was bound to our master plan, and they did not consult it."

Now the church is looking to get involved in the case, trying to protect its interest in building the new library. In court papers filed late last week, the church asked Judge Joseph Fratto to allow its Corporation of the Presiding Bishopric to join in as a co-defendant in the suit.

The five-floor, 250,000-square-foot library is planned for the northeast corner of North Temple and Main streets. It would house a growing historical collection, which currently includes 3.5 million manuscripts, 210,000 publications, 100,000 photographs and 50,000 audiovisual productions.

"We benefit from what our fathers have done for us, and we have the privilege through sacred records, which will be maintained here, to provide a legacy for those who follow," President Thomas S. Monson, first counselor in the First Presidency, said at a library groundbreaking ceremony in October.

Mangold, arguing before the Board of Adjustment, claims a parking impact study that the board considered in its decision was incomplete. She compared it to a similar study presented to the city regarding the Conference Center. That study foresaw that parking would likely only be impacted two weekends a year during general conference.