The rule is that if the adjective clause has only a single adjective, we should replace it before the noun e.g.: "the window that is broken was fixed by Tom" is reduced to "the broken window was fixed by Tom".
However, I have seen on several occasions the reduced clause placed after the noun, despite being single in the complete clause e.g.:
- The man responsible told me get out of here = the man (who is responsible) told me get out of here
- The people present started to shout = the people (who are present) started to shout
Is there any explanation for this?