Australia’s Senate voting system, particularly in Western Australia, is susceptible to corruption in part because of the “low-income earners” who work on the counting, according to the head of the inquiry into the state’s lost ballot papers.

Mick Keelty appeared before a joint committee on the lost ballot papers on Wednesday after handing in his report on the matter in December.

Keelty said there were attitude problems within the Australian Electoral Commission in the state and the lax procedures when it came to securing ballots meant it was ripe for corruption.

“You could easily imagine with the amount of money involved and the importance of the Senate so if you could foul up the outcome. Think about the people involved in this, not to be disparaging, people involved are low-income earners [such as polling booth staff], the opportunity for corruption is there. I have no evidence there was corruption but the system is so parlous,” he said.

Keelty’s findings on what happened to the ballot papers were inconclusive, with the former police commissioner saying they could have been accidentally thrown out, fallen off the back of a truck or become the subject of foul play.

When asked if he was shocked by what he found in Western Australia, Keelty replied: “Well I learnt a lot doing this. There’s some aspects that didn’t surprise me, the cultural aspects, having had the experience I’ve had … this isn’t being derogatory of colleagues in Western Australia or far north Queensland but there is a significant difference in culture in offices [over there] and what drives people in the office in Canberra and what drove people over there,” he said.

Keelty said there was an “attitudinal problem to accountability which was really worrying to me” and the same thing would not happen in the private sector.

He said AEC employees and volunteers did not seem to grasp the importance and significance of losing the 1,375 votes.

“Where things fall down is where clear guidelines and clear accountability is not known by individuals participating,” he said.

Keelty said most of the scrutineers had spent the entire day of the election in the sun campaigning for their respective parties and then were going into the “most important part of the day”.

He said what some of the polling booth staff who were employed just for election day were paid amounted to “beer money” and it was a case of mates getting other mates to participate.

“Scrutineers were saying they didn’t know what they were doing there but they had to be there and in a lot of places there was confusion about what their role was. They just had to physically be there, physically fill a spot,” he said.

Keelty said the votes were effectively moved around on utes and he was taken aback at how they were transported.

“I was so surprised at the outset in a world where we can track parcels from one side of world to the other that we don’t track these parcels,” he said.

The AEC had an offer from transport company Toll to implement a tracking system on the votes and the Perth office had referred the offer to head office but the federal election happened before a decision had been made.

Tracking votes which are being transported and moving to electronic voting were two moves Keelty strongly supported.

He said he was”relieved” that the AEC WA electoral manager, Peter Kramer, had stood down and staff had “let themselves down” by losing the votes.

“They’ve disenfranchised 1,170,000 people who have gone to the trouble of voting,” he said.

Keelty said a criminal investigation or commission of inquiry into the missing votes would be an “almost impossible task” as they would encounter the same obstacles as he did including destruction of evidence such as the boxes used to transport votes.