A resolution on getting rid of the upper house was defeated in a split decision at the party's convention last November.
But Wall — who supports scrapping the Senate — says a recent expense scandal has prompted some to ask that the issue be revisited.
"I've indicated what my personal position is, but if we're now going to try to advance it in some forums on the national stage, or with other governments, probably the first question I would get asked ... is, 'How do your members feel about it?'" said Wall.
Only a fraction of party members, about 250 people, voted on the resolution at the convention. There are about 12,000 Saskatchewan Party members.
The referendum is to be done over the next few weeks and the results announced in early July.
Wall says if the party supports abolishing the Senate, he'll push the issue at the annual premiers meeting in July and consider moving a constitutional amendment motion in the Saskatchewan legislature this fall.
"If we go with a mandate, not just from this particular process but from the people of Saskatchewan ... we could encourage all of the premiers of the country to have a free vote (in their legislatures)," said Wall.
"Maybe really it is time, not just because of the current scandal, but I think just because of what's been a long-running debate about the Senate."
The RCMP is examining the claims of several senators including Mike Duffy. Duffy left the Conservative caucus after it was revealed that the prime minister's chief of staff, Nigel Wright, wrote Duffy a $90,000 cheque to repay the senator's disallowed housing expenses. Wright later resigned.
Saskatchewan Sen. Pamela Wallin has "recused" herself from the Conservative caucus over questions about her expenses.
A constitutional amendment to abolish the Senate would need the support of two-thirds of the provinces representing at least 50 per cent of the population.
It could be a challenge.
Former Ontario premier Dalton McGuinty used to say the Senate should be abolished. But his successor, Kathleen Wynne, said Wednesday that she sees value in maintaining the upper tier of Parliament.
Wall himself used to advocate for Senate reform. His government passed legislation to allow the province to hold elections for senators-in-waiting. But the province doesn't want to pay for those elections and says Ottawa should pony up the cost because the Senate is a federal institution.
The premier says abolition will be difficult, but he's now come to believe reform is impossible.
"We'd all like to see a meaningfully reformed Senate ... an equal body, where each province has equal representation," said Wall.
"That's what meaningful reform means. I'd like to see that too.
"I'd also like to see money trees in Saskatchewan (and) they're not going to happen.
"It's just not going to happen."
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