The controversial Cum Ex tax transactions with possibly billions of tax fraud are causing a stir again. The opposition in the parliament of North Rhine-Westphalia accused the CDU-FDP government of misconduct. In the opinion of SPD faction leader Thomas Kutschaty the government sets wrong priorities, which led to scarce personnel with the clarification of Cum Ex cases and threatening statute of limitations of first cases.

Kutschaty considers it inappropriate for the country to work against shisha bars and their alleged tax fraud on weekends with more than 1,000 officials. Such a prioritization has "populist character," he said. The focus should instead be on Cum-Ex, the "biggest tax robbery in the history of our country".

According to research by WDR and "Süddeutsche Zeitung", personnel shortages at the authorities have led to the mountains of Cum-Ex cases not being processed years later - a large number of cases took place between 2008 and 2011. Now threaten in some cases prescription. That would be a "huge scandal" from Kutschaty's point of view.

The Greens looked similar. Its budget spokeswoman Monika Düker said it would not be public to the public, if the tax fraudsters because of a lack of staff in authorities unpunished. Left-wing MP Fabio De Masi said a statute of limitations would "massively damage confidence in the rule of law."

In the case of cum-ex-transactions, investors shift shares with ("cum") and without ("ex") dividend entitlements between participants around the dividend cut-off date. In the end, the treasury is no longer sure who they belonged to. The result: tax offices reimburse capital gains tax several times, although the tax was paid only once. Whether this was illegal has not yet been clarified by the highest court. It was not until 2012 that the federal government changed the practice of paying the dividend tax in such a way that the trick no longer worked, at least in its current form. The damage at the expense of the state should go into the billions.

"Some procedures could not be tackled yet - if there should be facts from the year 2008, we have statute of limitations problems," warned Sebastian Fiedler, head of the Federal German detective agency (BdK). "Cum-Ex must have absolute priority - that has missed the state government so far," he said. "In case of need, other things have to stay down first so that you can finally make headway with Cum-Ex."

The Ministry of Finance, on the other hand, emphasized that the fight against tax evasion was "very important in the list of tasks of the state government". Indications of a threat of limitation are not known. The ten-year limitation period for tax evasion in a particularly serious case could be extended to up to 20 years by an interruption - such as a search.

But BdK boss Fiedler pointed out that this applies only to the procedures that are already in progress and not just for the numerous procedures in which due to the shortage of staff could not even begin the investigation.

The state of North Rhine-Westphalia plays a key role in the Cum-Ex scandal: in Bonn sits the Federal Central Office, which reimbursed the taxes. In addition, the Cologne prosecutor is the lead law enforcement agency.

According to information from the WDR, the Greens and the SPD have now requested a current quarter of an hour in the Legal Affairs Committee, which will meet next Wednesday. Then the state government should describe their view of things.