The bishops in question are in Canada, and their concerns regard a campaign against the Harper government's plan to sharply reduce international aid funding:

OTTAWA Canadian Catholic bishops have taken the unprecedented step of blocking an annual education campaign organized by the churchs foreign aid wing, Development and Peace, after deeming this years edition too partisan.The bishops are reported to have been concerned that the campaign, targeting the Harper governments controversial changes to Canadian international assistance, would divide parishioners and hurt the churchs work with the Conservatives on other issues.Organizers say they can appreciate the bishops concerns and are toning down the campaign so it is less political.

We certainly wouldn't want the church to appear to favor one side.