Nancy Pelosi (D-Calif.) had served in the House for only six months when she first caught the attention of Rep. John Murtha (D-Pa.).

It was December 1987, and then-Rep. Austin Murphy (D), whose Pittsburgh-area district neighbored Murtha’s, was facing an ethics reprimand on an array of charges that he had violated House rules. Despite Murphy’s pleas of innocence, a vast majority in the chamber voted for the wrist-slap. Pelosi stood with Murtha and 65 other lawmakers in opposing it.

Over the two decades since, the unlikely bond between the polished San Francisco liberal and the gruff, conservative retired Marine has proved among the most critical to Pelosi’s ascent to Speaker.

Now, as Pelosi pivots from the CIA interrogations flap to face the potentially more vexing problem of how to contain the controversy surrounding Murtha and his earmarking empire, an alliance forged confronting one ethics challenge will be tested by another.

So far, Democrats close both of them say, the cascade of headlines about Murtha’s network and the federal probes of contractors, lobbyists and at least one lawmaker in his orbit have had no effect on their relationship.