First let me clarify – I’ve nothing against HR and their involvement in the hiring process. What I object to very specifically are two habits: letting HR choose who gets interviewed, and letting HR do the first interview and veto some of the candidates before they ever meet the technical writing team leader.
I object to both habits on the same grounds: HR don’t really select people by their technical ability, they select them by how well their personality seems to fit the job. But so many companies don’t employ writers that many HR – even very experienced ones – have never hired one before and don’t know what the job entails. They therefore may select by how well the candidate fits a different job, one they’re used to hiring for – developer, QA or even HR.
The problem, then, is that you’re missing out on some excellent writers, and getting excellent candidates for roles you’re not trying to fill. So by all means, give HR their fair vote – but don’t let them select who you interview.