There are a number of problems with this particular philosophical question, the most obvious one being that we don't have a single definition of free will. (We have many, some of which are contradictory, but what we don't have is a single agreed definition that we can then actually test against.)
A second problem lies in the fact that science is based on observable phenomenon, falsifiability, measurement and invariance. You can't observe free will directly, so we'd need something we can observe that is a surrogate. That's fine, physicists do that a lot. Only, what do we observe or measure here? Without a working definition and model, we don't know what to look for or how to quantify it.
Unless we can distinguish between random, hidden variables, undiscovered interactions and choice, free will is unfalsifiable. In principle they can be distinguished, since free will implies that a variable that is actually independent as far as the physics is concerned can affect the outcome. In practice, since we only know a variable is independent experimentally, you can't readily distinguish between free will and simply getting the physics wrong.
We do have one possible path, Professor Conway's Strong Free Will Theorem. This is a dense mathematical argument that essentially states that free will can only exist within the universe if physics itself has a notion of free will. If something that is fundamental within the universe has the capacity to behave in non-random, non-deterministic ways, then this can potentially accumulate into free will in something as complex as a brain. If there is no such capacity, there is no free will.
This part's fun, since physicists don't know if this would be fundamental particles, superstrings, M-branes, pure mathematics or something yet to be determined. So once we know what "fundamental" means and what the physics is at this level, we can presumably figure out how to do some experimental test that can rule out all of the alternatives.
And, of course, it relies on both the theorem being correct in all the particulars AND of there being nothing that can be considered "outside" of physics/mathematics.
Now, if we can get past all of that, then we can determine if there is free will. But at this point, any answer is essentially meaningless.