The special counsel, Robert S. Mueller III, has approached law enforcement consistently for decades: leading aggressive investigations marked by adherence to precedent and higher office.
The spy agency does not believe its Russia informants have been killed, but sources have gone largely dormant amid heightened scrutiny and rising threats.
As he faces mushrooming legal troubles, the president evokes a place replete with shady businessmen and mob-linked politicians, raffish types with unscrupulous methods and uncertain loyalties.
The president’s high-profile pardons and commutations this year prompted his lawyers to caution him against weighing clemency for associates in the special counsel investigation.
Fearing more shoes will drop, Republican leaders have begun urging some incumbents to speak out on President Trump’s misdeeds, while Democrats stress a “culture of corruption.”