The presence of the lagged shadow policy rate in the interest rate feedback rule reduces the government spending multiplier nontrivially when the policy rate is constrained at the zero lower bound (ZLB). In the economy with policy inertia, increased inflation and output due to higher government spending during a recession speed up the return of the policy rate to the steady state after the recession ends, which in turn damps the expansionary effects of the government spending during the recession via expectations. In our baseline experiment intended to capture the effectiveness of the American Recovery and Reinvestment Act of 2009, the output multiplier at the ZLB is 1.9 when the weight on the lagged shadow rate is zero, and 0.5 when the weight is 0.85.