 Why are the police willing to risk the life of Gerri to kill Lane?
The humming paragrav-paks embedded beneath his shoulder blades held him motionless above Newyork's three administrative towers. Two black paragrav-boats whirred along the translucent underside of Newyork's anti-missile force-shield, the Shell. Lane dropped lightly to the floor, inside the room, in battle-crouch. Lane is an insane killer. Lane's mailed hand snapped open a pouch at his belt. A loudspeaker shouted into the room: "Come out of there, Lane, or we'll blast you out." The cannon trundled into the Square on its olive-drab, box-shaped caterpillar mounting and took up a position equidistant from the bases of the three towers. "Lane is holding the Martian Ambassador, Gerri Kin, hostage.
 Lane is too dangerous to be left alive. They can't risk him escaping just so they can rescue Gerri.
 Lane is too dangerous to be left alive. They can't risk him escaping just so they can rescue Gerri.  They think Lane may be infected with a biological weapon.  The police don't care if they kill Martians.  They don't believe that Gerri is in the room with Lane.