On 16 June 1995 Spahn, in his analysis of the original idea, concluded that the concept was not viable and suggested an alternative solution to the problem of managing exchange-rate volatility.
The mechanism allowing the identification of abnormal trading in world financial markets would make reference to a 'crawling peg' with an appropriate exchange rate band.
[4] In November 2004, Belgium submitted this law for an opinion to the European Central Bank, which provided both an economic and legal assessment.
Its summary stated: "...the ECB concludes that the economic and monetary usefulness of a tax, such as envisaged by the draft law, is highly questionable, given the uncertainty of its claimed benefits and the likely welfare costs arising from distortions in the working of financial markets.
"[4]It continued: "...the ECB is of the opinion that the introduction by a euro area Member State of a tax, such as envisaged by the draft law, is incompatible with the Treaty.