My daughter just completed the law school admissions cycle with a 3.88 LSAC GPA and a 172 LSAT and she attended a top 20 undergraduate school. It is impossible (for us anyway) to know for sure but it does seem as if the most elite undergraduate schools do receive some very minor boost in terms of GPA. By “very minor” I mean maybe between 0.05 and 0.1. It is going to be the combination of your GPA and your LSAT score which influences which law schools admit you. For Harvard Law you are going to need an extremely strong LSAT score as they are notoriously focused on the numbers and keeping their LSAT median at 173 really does not give them much latitude in admissions decisions. The LSAT is fundamentally different than tests like the ACT or the SAT so as you get closer to taking the LSAT you should probably take a diagnostic test to better understand how much test prep will be required. It is extremely difficult to predict Stanford Law admissions decisions. Stanford and Yale both have relatively small incoming classes and they have scores of 175+ LSAT / 4.0 students to pick from. When you look at the profiles of students admitted to Stanford Law you do see more variance in terms of both GPA and LSAT score. I don’t pretend to know what Stanford Law is looking for but it is something more than just strong GPA and strong LSAT
Money and career plans factor into many law school students ultimate decisions on where they go to law school. It is very common for students to apply to many, many law schools to “blanket the T14” as the saying goes. When you do this with strong stats your going to find scholarship offers of $120K to full tuition+ at lower ranked T14 schools vs. full price at other schools. It is important for you to understand what limitations the law school you attend might have on your future career and to weigh that against the net cost of attendance. My daughter was forced to chose between NYU at sticker ($300K), Columbia with $65K scholarship (net $235K) and Duke with $120K scholarship (net $150K) in the final decision
Long winded answer but provided your GPA is not well below a law schools median or 25th percentile its the combination of GPA and LSAT that will really matter. There are not many doors closed to you if you had a 175 LSAT to go with your Harvard 3.7. If you scored 170 on the LSAT you’re going to have a touch time getting into some of the T6 schools with that 3.7 GPA. If you score 165 on the LSAT you might struggle to get into any T14 schools.