Noticed flags flying at half-staff Sunday, May 15? Two recent proclamations from President Joe Biden explain why.

Biden has designated May 15 as Peace Officers Memorial Day, and the week in which it falls as Police Week. Within his proclamation, Biden called on all governors to direct flags to be flown at half-staff on Sunday.

This comes a day after Biden ordered flags to be flown at half-mast in memory of the one million American lives lost to COVID-19.

Under this order, issued Thursday, flags are to remain at half-staff until sunset on Monday, May 16.

While the president has the power to order flags lowered to half-staff after tragic events, it’s not yet clear if Biden will make such an order in memory of the 10 people killed in Saturday’s mass shooting in Buffalo.