When Twist is talking to Johnson at Johnson's desk, Johnson is not wearing his committee badge, but in the next scene when they are walking outside the cells, Johnson now has a badge on.
When the prisoners hold their soiree with the female guests there is a light waltz playing in the background, but when we see the orchestra there are no stringed instruments visible - only brass instruments.
When Johnson and Sykes are at Slim Charlie's cafe just before they make the phone call to the police station the shadow of the boom microphone falls across Will Hay.