Chefspec fails where knife and chef don't on untrusted certificates

I am using a private supermarket. If I run chef install Policyfile.rb there are no issues and a policyfile lock is created and I can then run rspec without issue. If I delete the policy file, running rspec throws the following error:

An error occurred in a `before(:suite)` hook.
Failure/Error: raise"Failed to generate Policyfile.lock", error)

  Failed to generate Policyfile.lock

If I use knife ssl verify https://chef-internal-mrkt/, verification passes without issue. Why does rspec not follow suit and ignore the imported certificate?