I'm sorry but this is not a good excuse for what essentially seems like age discrimination on the part of CC. Perhaps not legally, but absolutely so morally.
The fact that they accept some people who are older is no excuse for having a policy that systematically disadvantages older applicants. Their own wording on the website strongly suggests non-priority, or older, applicants have to be much better than the priority candidates to be considered. So, older applicants have a higher bar. That is discriminatory.
Now, some people say oh but there could be older undergrads so technically it is not discrimination. I am not a lawyer (but I suspect even the law would look at the discriminatory impact of the policy and not just the 'intent') but morally speaking that is a baseless defence. 95%+ of their priority group are younger than their non-priority group so there is clearly a discriminatory impact on older applicants. An older applicant applying to CC has every reason to believe they will be at a disadvantage. Many will be turned off from applying right there.
I have no dog in this fight. I did not apply to CC and would not have wanted to even if they did not have this policy (they are an amazing firm in many ways but just not my cup of tea) But as future lawyers we, even more than others, should care about equality and age should surely be treated as a protected characteristic just like race, gender or faith. If there was a policy that clearly disadvantaged people who had one of those latter characteristics, even if the policy was targeting something else, we would rightly be worried. We should be worried here too.
Why? Age discrimination is an increasing problem as a whole host of industries are transformed by tech and stereotypes about age and technical capabilities bleed into hiring/promotion decisions. One would have thought a law firm like CC would have paid some attention to this.
Putting aside what is right (and legal) for a bit, and acknowledging that every private company gets to decide what is smart and the market will reward/punish it accordingly, this decision to prioritize younger applicants will probably hurt CC in the long run. People who are more mature and have had a chance to think through their options will likely stick to law longer than someone who was tied into a TC at 18. What of the transferrable skills that career changers can bring? By basically signalling to these groups that their applications will be deprioritized, CC is ruling itself out of the running for these candidates (yes I know every firm had their choice of amazing candidates but they are systematically ruling out big groups with quite different skills and temperaments).
So just on the business case alone this seems like a very strange decision but the more important point is a law firm of all places should not have such a discriminatory policy even if they can 'technically' get away with it by finding the right loophole etc. The morality of their move is frankly quite damning. The legality of it I am looking forward to exploring as I start my law studies but I will be very disappointed if I find the law would allow for this kind of behaviour.