https://www.timeshighereducation.com/news/professors-oppose-use-peer-review-reports-tenure-case
No, tenure committees should not rely on peer review reports on professors' article and book submissions. Here's why:
The peer reviewers usually evaluate an initial submission, NOT the finished product (which often gets modified to address reviewer concerns). For tenure purposes, only the final product should matter. To adapt a metaphor from Bismarck, the tenure committee should focus on the finished sausages the candidate produced, not the often ugly process by which they were made.
In most cases, neither the author nor the tenure committee can really know who the peer reviewers are (they are supposed to be anonymous, though admittedly sometimes the anonymity gets breached). Thus, it's hard to say how much standing they have in the profession, and how much weight to give to their views.
Some journals do a terrible job of selecting peer reviewers. It's bad enough they influence publication decisions. They shouldn't influence tenure decisions, too.
Tenure committees already used outside reviewers to evaluate candidates' finished scholarship. The committee can choose an appropriate expert, and that person can evaluate the finished work, not just a draft submitted for initial review.
If journal and/or book peer reviewers know that their reports might be used to judge tenure cases, they might skew their reports to help their friends get tenure and/or try to deny it to their enemies. This likely happens to some degree, anyway. But using these reports for tenure purposes will make it worse. While authors usually don't know who the reviewer is, the latter often know who the author is, including even in cases where the process is double blind (if X is known for writing about subject Y and reviewer is familiar with X's other work on that subject, the reviewer can often guess X is the author of a given submitted article on Y).