Does a ban on the short selling of securities or uncovered credit default swaps make sense?

Was short selling a cause of the financial crisis and should bets on falling stock prices be banned as a result? Andre Horovitz, Financial Risk Fitness GmbH, asserts that also short selling and non-backed CDSs can make sense for businesses without our having to assume a gambling motive. At the same time he favours necessary regulations for the financial markets. Martin Schütte, University of Munich, points out that the world financial system almost collapsed two years ago because of the uncontrolled growth of markets for speculative financial products. Now there is a danger of the same thing repeating itself. In order to prevent this, a prohibition of particularly dangerous products must be considered. For Barbara Hendricks, SPD parliamentary party, a prohibition of short selling of securities and uncovered credit default swaps would make sense with regard to necessary regulations, but would be an inadequate instrument. Sigrid Müller, Humboldt University of Berlin, maintains that bans on short selling cannot prevent stock market crashes. Their effect instead is to intensify a crisis. Furthermore they reduce liquidity and lead to a loss of information efficiency. She proposes a registration obligation as a regulatory alternative. Max Otte, Worms University of Applied Science, maintains that a prohibition of short selling of securities and uncovered credit default swaps are reasonable components of a comprehensive financial market regulation that must also include meaningful capital requirements, the taxation of financial transactions and the regulation of business models and products.