You have to, unless you want to use the duty solicitor who's a free resource. The duty solicitor should be perfectly fine for most situations unless you really actually are guilty, or you think you've been stitched up, to use TV crime drama parlance.

> The duty solicitor should be perfectly fine for most situations unless you really actually are guilty

But should you choose to use your own solicitor, it may adversely harm your defense, because innocent people use the duty solicitor...