An audit of Wallin's spending flagged more than $121,000 in inappropriate expenses and called for further review of nearly $21,000 in additional claims.
Wall says he'll have to see how it all works out, but he is disappointed to hear the dollar amount.
The premier says it's a reminder that people in public life need to be careful about spending taxpayers' money.
Wallin has repaid $38,000 and has said she will pay back other disallowed expenses with interest.
Wall used to advocate for Senate reform, but said this spring that he's now come to believe reform is impossible and the upper chamber should be abolished.
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