I dont think Doctor Who can really crossover with anything, but they could do a Whoverse Law&Order like they have done Eastenders.
Actually I think Doctor Who is probably the easiest show to crossover to another franchise. He would fit in anywhere.
Typically an episode of Doctor Who starts with the guest cast, and then about 5-10 minutes into the episode the Doctor and companion(s) show up for no reason. That format would work for anything.
in theory yes, but when you think about it, no.
think about it, all those very public alien invasions, when did that happen in the Law & Order time line? British society in the Whoverse (& most likely the whole of humanity) is very different in the Whoverse than it is in the real world, something that is not seen on Law & Order.
It is bad enough that Without a Trace never refrenced the Cabbie Killer of CSI NY, despite being in the CSIverse, for a show that is apparntly set in the Whoverse not to metion the alien invasions is just crazy.