Public safety networks are desired to meet increasing demands for sharing images or videos among first responders and incident commanders. Long term evolution (LTE) is considered a candidate to achieve such broadband services. However, in the case of a disaster or a big sporting event, the traffic suddenly increases sharply as the number of active public safety users increases. This paper reports methods for allocating radio resources for device-to-device (D2D) communication as a means to enhance system capacity of the public safety LTE (PS-LTE). The methods allow spatial reuse of the resources among D2D communicating public safety users satisfying certain sharing conditions. Two practical scheduling algorithms that take into account both spatial reuse of the resources and fairness between the D2D communicating users are described. System level simulation results reveal that the methods can increase the number of users that satisfy the throughput requirement for video transmission.