We’re seeing similar trends across all House committees. On average, the number of communications aides on House panels has increased by about 40 percent since 2001, while the number of policy-focused aides has stagnated. Senior committee staff are down 15 percent over the same period. Many find this concerning because as Congress keeps cutting its senior staff, on Capitol Hill, organized interests and their lobbyists can increase their sway over lawmakers.

Senate committee staffing shows a similar pattern: a 20 percent increase in communications staffers, a 5 percent drop in policy staff and a roughly 30 percent decline in senior staff — even as committee staffing overall has shrunk by 15 percent.

Here are three reasons committees might be deploying staff like this.