Can you read Best Served Cold even though you haven't read the first law trilogy? My birthday is in a few weeks and I am trying to give the Mrs some ideas for birthday prezzies.
You *can* but I doubt you would want to. The first three serve the purpose of laying lots and lots of groundwork and drawing you in. BSC is a self-contained book, and you would most likely still enjoy it, but there's a lot of stuff you'd get from the first three, including some characters.
I'd heartily recommend reading the first three first.