The facts in the case are 'muddy'.
The recording sounded 'muddy'.
His shoes were 'muddy'.
(..) Your man's a defector, Guillam. Turned by the opposition months ago and now they've sent him back to us. - What for? - Never mind what for. To muddy the water, that's what for. To spread a whole lot of damn nonsense to get us chasing our tails. The point is this. He's heading for home. (..)2011 Tinker Tailor Soldier Spy