Both Uses of

condemn

in

Lord of the Flies

The derisive laughter that rose had fear in it and condemnation.
p. 86.1 *

condemnation = strong criticism

On the other side of the island, swathed at midday with mirage, defended by the shield of the quiet lagoon, one might dream of rescue; but here, faced by the brute obtuseness of the ocean, the miles of division, one was clamped down, one was helpless, one was condemned, one was— Simon was speaking almost in his ear.
p. 111.2 *

condemned = forced into an undesired situation

Definitions:

(1) (condemn as in: She condemned their plan)
express strong criticism
(2) (condemn as in: was condemned to life in prison)
force into an undesired activity or situation -- such as to legally sentence someone to punishment

or:

find guilty -- especially in court (and sometimes to death)

or:

provide the means of finding guilty
(3) (condemn as in: condemned the building)
an official government finding that a building is not suitable to be occupied