THe instution that allowed a stock market crash, that was expected to be another recession to turn into a depression. Bywhich should of added more money into the economy to stimulate spending, growth and eventually decrease unemployment. Failing to do this, the money supply in the banks fell short of expections, which caused a run on the banks. Which then further worsened the crisis.
The Federal Reserve controls interest rates to loans given out to banks, in order to control the money supply.