'we' - us. Either whoever the speaker is addressing or the group or prganisation that on whose behalf to speaker is making this statement.
'should recognize' - ...we need to understand or acknowledge or allow or accept
'the public's right' - the right of ordinary people
'to be informed' - to be educated (about)
'and critcize' - and to comment (on/upon)
'environmental information' - the subject about which people should be informed, and about which they should be allowed to comment freely.
So, to re-phrase the sentence: 'We need to accept that people should know about environmental information and also be able to comment freely about this information.