You can't, in any real way.
You can detect that there is a pointing device:
SelectQuery selectQuery = new SelectQuery("Win32_PointingDevice");
ManagementObjectSearcher searcher = new ManagementObjectSearcher(selectQuery);
foreach (ManagementObject pointer in searcher.Get())
{
Console.WriteLine(pointer.ToString());
}
But you can't tell if it works until the user moves it, and / or clicks the buttons.