Law: For seniors not pursuing law school but seeking legal jobs, most entry-level paralegal and legal assistant positions hire in mid/late spring. There are a few prestigious legal opportunities with fall deadlines, including the Mintz Project Analyst Program and the Kobre & Kim Analyst program. Keep an eye on #GIALP newsletters for announcements about these earlier recruiting opportunities!
Government: Most entry-level jobs in government are posted in the spring, and are looking for people to begin work immediately (so not looking to hire in January and then wait 6 months for the candidate to graduate). This is largely applicable to federal, state, and local hiring, but we encourage you to meet with Career Education to talk about your specific goals and drill down into possible differences between government agencies. For example, the Department of Justice often posts entry-level paralegal roles staggered throughout the spring, so those aren't all technically for "immediate hire", and a great strategy is to set up a Saved Search for these opportunities on USAJobs in the fall. The most notable exception to the spring hiring rule is in the intelligence community, where the screening and background check process can take many months, so if those roles interest you, you would want to look into intelligence opportunities as early as possible (at least a year in advance) to learn the timelines for the specific intelligence agencies you are pursuing.
Think Tanks: Some of the larger think tanks may post entry-level opportunities in the early spring semester (with deadlines as early as January), but this can vary from year to year and from employer to employer. Think tanks more often post entry-level opportunities in mid-late spring.
Fellowships: Overlying all of this is fellowships, of course! There are many, many fellowships geared toward people pursuing careers in government and policy, so we encourage you to have fellowships on your radar this summer and fall, and then move on to applying for spring opportunities as needed after considering/applying for fellowships in the fall.