Google punishes websites that use black hat seo to get their ranking up on google, some SEO teams use spammy keywords to get their google rank up, they use the same word over and over again on a forum or something to rank their page up on google.

If you were to use white hat seo for your company and then using black hat seo for someone elses website, copy and pasting loads of backlinks to someone elses website that you were competing with, then wouldn't that bring them down on the ranking and bring you up on the ranking?

Would google find out that you were doing this to peoples websites? If they can't identify who a user is on a forum giving loads of spam backlinks to a website then wouldn't that give you an easy way to bring your competitors down on Google?