These companies, or their legal representatives, will likely argue that their affiliated drivers are typically independent contractors, not employees. But don’t’ let that argument stop you from fighting for your rights. The specifics of the case, like the driver's status at the accident time, are what will ultimately determine liability.
Keep in mind that Uber and Lyft both require drivers to have liability insurance, usually worth about $1 million. That shows that you may still have options to pursue compensation whether or not the at-fault driver was an independent contractor.