WAPOU members voted to empower their executive team to call for strike action at a meeting on Wednesday afternoon.
Mr Welch, who spoke to the Courier shortly after the vote, said the verdict was unanimous.
‘(We will strike) unless the Government is able to put an offer on the table that is acceptable,’ he said.
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READ NOWMr Welch said while the details of possible strike action had yet to be ironed out, it was highly likely that action would include Casuarina staff.
‘I would expect it will effectively involve most, if not all prisons,’ he said.
‘We’ve been trying to get a deal since September of last year.’
Mr Welch said the decision to strike solidified after nurses finally ironed out a wage increase agreement from the State Government after they closed one in five hospital beds, a move Premier Colin Barnett said could have cost lives.
WAPOU members have previously rejected a 9 per cent pay rise.
Mr Welch said striking was not the WAPOU’s ‘preferred approach’.
‘(But) our members asked, ‘why are we sitting around while other unions are taking strike action?’,’ he said.
Around 97 to 98 per cent of prison officers in the WA system are union members, which could lead to mass walk-outs.
Mr Welch said if a strike did take place, WAPOU would ensure health services to inmates and ‘appropriate perimeter security’ was maintained.
‘We will not risk the security and safety of the general public,’ Mr Welch said.
‘Our members are angry and we want to show the Government very clearly how angry they are.’
Opposition Corrective Services spokesman Fran Logan said Colin Barnett ‘had made a rod for his own back’ by agreeing to raise nurses wages by 14 per cent.
Mr Logan said that since Christmas, 20 prison officers had been hospitalised or injured in attacks by inmates.
Mr Barnett said the State Government would not cave in and make a pre-election offer to prison officers.
He urged WAPOU members to wait until the election was over to continue negotiations as their industrial agreement did not expire until June 10.