A chronology of Lawrence Murphy is available on the Archdiocese of Milwaukee Web site at www.archmil.org.It literally and unhelpfully links to the site's home page, and let's you search, rather than linking to the Lawrence Murphy Chronology.
The chronology's mid-to-late-1990s entries might now be supplemented from the news reports involved in the controversy over the ecclesiastical proceedings at that time.
I'll supplement the early-to-mid-1970s enrtries with these two items.
"Murphy’s actions were public knowledge and reported to civil authorities as early as 1973; in newspaper articles as early as 1974; and through civil court proceedings as early as 1975." according to a statement from Archdiocesan spokesman Jerry Topczewski in the October 13, 2009 Milwaukee Catholic Herald.
"[then-Archbishop Will1am] Cousins testified he found nothing in his investigation to substantiate any of the complaints about Murphy. That testimony came in a 1975 sworn deposition in a civil lawsuit filed by a victim. Murphy 'sacrificed himself for the school' after 'harassments and threats,' Cousins said under oath. The lawsuit was dropped." according to the March 26, 2006 Milwaukee Journal Sentinel.
It would make sense for our Archdiocese to say it could not have been involved in a cover-up if by 1975 it was "public knowledge" that Father Murphy had been sexually abusing kids. It's just hard to square that with Archbishop Cousins, under oath, denying Murphy's actions that same year.
Update: The New York Times posted The Document Trail of the Vatican proceedings against Father Murphy. (via Paul Moses at dotCommonweal)