Short-selling allows investors to profit from asset declines. In the events of market uncertainty, short sellers are frequently accused of abusing the increasingly volatile market by betting on declining stock prices. To prevent further market downturns and calm the volatile markets, regulators around the world have put constraints on the ability to sell short. During the financial crisis (2008) and Covid-19 crisis (2020), the restriction became a popular method amongst economies to stabilise volatile stock markets, with South Korea holding the most extensive ban during both crises. Although commonly used, the policy has been questioned for its effectiveness. This thesis studies the effectivness of the ban by observing the correlation between the existence of ban and price volatility of South Korea's biggest index, KOSPI200. We use an ordinary least squares (OLS) method and apply these in a two-stage analysis to disentangle the effects of crisis and ban. By doing this, enabling to isolate the effect of the ban. We find evidence contradicting regulators incentive to ban short-selling as the effect of the ban is not strong enough to compensate for the effect of the crisis.