This paper investigates whether an Islamic screened benchmark index shows a different risk adjusted performance in comparison to a non-screened benchmark index. In contrast to other papers this study analyzes daily observations in the years from 2007 to 2012, a period heavily affected by the financial crisis. The Capital Asset Pricing Model and the Jensen measure of abnormal returns are used to estimate and compare the indexes mean risk-adjusted returns. The results show that the Islamic index does not reveal any different level of daily mean risk-adjusted returns compared to the conventional non-screened index. Hence, Muslims who align their investments according to the teachings of Islam are not worse off than non-restricted investors following the screened Islamic index.