Since the 1990s, members of the US House have shifted resources away from legislative functions to representational activities. We reveal this decline using an original dataset constructed from 236,000 quarterly payroll disbursements by 1,090 member offices for 120,000 unique staff between the 103rd and 113th Congresses, as well as interviews with former members and staff in Congress. These data allow us to test two plausible alternative explanations, one rooted in the centralization of legislative power over time and the other in conservatives’ desires to contract government power. We show that the decline in legislative capacity is symmetrical between and consistent within both parties, contrary to expectations rooted in asymmetrical, ideological sabotage. Additionally, this divestment occurs within incumbent member offices over time, accelerates when new members replace incumbents, and persists when majority control changes. We conclude that competition over institutional control and centralization of legislative functions motivates declining legislative capacity among individual members.

From the article:

The general patterns we uncover here are substantiated in an interview with a Legislative director for a democrat, who serves as a senior staffer responsible for the office’s legislative matters and manages three junior colleagues. the staffer observed that the decline in legislative resources we document here is associated with increased turnover and decreased policy experience in the House:

The other piece is no one really knows how to legislate anymore. as someone who’s been around a little while…there’s not really the expertise, even among committee staff that there was a couple years ago because we’re not doing it [legislating]…i was talking to a [committee legislative staff friend] last year. she was telling me that she had to bring all of [the legislative assistants working for members on] the subcommittee in to teach them how to do a markup because not one of the [legislative assistants] of this subcommittee had ever staffed their boss in a markup before. ever.

[…]
We’ve got a great, smart team … but two of my legislative assistants are 23 and 24…you need a little bit more experience in a place like this. [Congress] is always gonna be a young place, it’s always gonna attract young people that are ambitious. But it’s gone to an extreme…you can tell that people haven’t gone through this before sometimes. sometimes you can use that to your advantage, sometimes it’s frustrating. But that’s a real issue…it’s hard when there aren’t people that have been through quite a few markups, or been through a couple reauthorizations of a major bill

For more information, see the many posts at the Bessette-Pitney blog that have discussed declines in congressional capacity.