It is this realization that leads him to make the decision to allow the man to escape.
Older than his colleagues, wise in his understanding of the probability that their man will try to escape by boat, our policeman has his eye on the reward and the likelihood of promotion in the start of this play. Encouraging his co-workers to do their duty, he sends them off to put up other Wanted posters, while choosing to stay at the quay alone in wait of the revolutionary.
When his man does indeed turn up he is disguised as a ballad singer and the policeman doesn't realize who he is. Claiming to be in town due to the fact that they are holding the assizes, which gives him the opportunity to make some money, the revolutionary tries to get past the policeman but is refused access. It is at this point that he tells the policeman, while pointing at the poster of the wanted man, that he knows who the revolutionist is.
Fear is the first factor that the man uses to enforce his plan to get past the policeman, which persuades the policeman to allow him to stay. "There's not a weapon he doesn't know the use of," he says, "and as to strength, his muscles are as hard as that board." ('The Rising Moon', p. 907). And the second is complicity.
And, as they sit together, back-to-back, while smoking their ...