An investigation into German Chancellor Olaf Scholz over his possible role in assisting a bank to commit tax fraud was shut down by lawmakers on Wednesday.

The probe says that, during his term as mayor of Hamburg between 2011-218, Scholz among other politicians assisted M.M. Warburg Bank to avoid paying back falsely claimed tax refunds, which cost the government over 40 million euros.

MPs from the conservative opposition CDU and CSU presented the case and pushed for the establishment of a parliamentary commission to look into the case. However, members of parties from Scholz's coalition passed a motion to reject the proposal.

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CDU and CSU hinted they will appeal the decision at Germany's Federal Constitutional Court, noting that their rights as the opposition were not respected.

The Chancellor is already the subject of inquiry about financial violations carried out by banks and stock firms in Hamburg in 2016. 

Known as the "Cum-Ex" or "German Dividend Tax Scandal", a 2017 trading scandal exposed a large number of German companies and personnel, including government officials and diplomats, for committing tax fraud where they rebate tax returns multiple times for a single payout.

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The tax scheme, which has left several European countries with losses worth billions of dollars, was banned by Germany in 2012.

Warburg eventually was forced by the government to pay back tens of millions of euros during the term of former Chancellor Angela Merkel.