If you ever get to hear Justice Ian Binnie speak about being a lawyer or about advocacy you can be assured that at some point early in the speech he will speak about Bert McKinnon (that's McKinnon ACJO to the rest of us). Binnie articled with McKinnon and spent the formative years of his practice working underneath a man who was one of the greater advocates of his day. What you have no doubt about in hearing Binnie speak is that McKinnon was his mentor and that without his guidance Justice Binnie's career would have taken a very different shape than it did (not necessarily a worse shape -- but a different one).
Not every lawyer will have a mentor or a mentoring relationship as strong as the one that existed between Bert McKinnon and Ian Binnie. That situation takes a particular combination of talents and personality -- particularly on the part of the mentor -- that is hard to find on a routine basis. Nevertheless, a key aspect of survival in the legal world is finding a mentor.
First let me say that a mentor is not a protector. There are many students and junior associates, particularly in the larger firms, that make the mistake of thinking that because they have a favoured relationship with a more senior partner that they are therefore protected from the pitfalls of not being hired back ro not making partner. This is a drastic misread of the way law firms and the law business works. The relationship that exists between partners is one that even the greatest of warm feelings by a single partner, or even group of partners, is not enough to overcome the opposition of other partners -- unless that opposition is lukewarm. The reality is that most senior partners if faced with serious headwind about a favoured student or associate will shrug their shoulders and think that what is happening is regretful but not do much more. They are going to save their ammunition for allocations.
A mentor is in fact a teacher. There is a great deal about any law firm and the world of law generally that is opaque until it is explained by someone who is in the know. That in the know can be about very pragmatic matters (for example, in the early '90's in Toronto knowing which judges to call M'Lord) or quite idiosyncratic (which partners have long standing grudges that go back decades). More often than not though at the beginning the teaching is 'word to the wise' teaching about firm culture, about comportment and about one's own evolving circumstances. As you progress further the teaching becomes more substantive about law, skills and techniques.
For the most part you will not have a single mentor. When articling some of the best mentors are the associates a few years ahead who still remember what articling life is really like and can give some useful guidance about how to survive the seemingly arbitrary world of articling. Having survived that process it is then that you will generally find yourself engaging with the more senior people and them engaging with you.
In my case I still clearly see Ron Slaght taking the time to show me what a mess I had made of the first statement of claim I had drafted and then explaining to me how to properly draft a claim -- know the law but tell a story. There is not a single pleading that I sit down to write where I do not think of Ron's advice. What I also appreciate more now is that likely it would have been easier, cheaper and less troublesome for him to have said thank you for the work and then redone the claim himself. It was the taking the time to explain what was done wrong and then how to better approach it that made him a mentor rather than just a senior partner. It was not long after that that Ron headed out to set up Lenczner Slaght and so no lasting close relationship ever had a chance to develop there, but the willingness to take the time to teach is the key character in identifying a good mentor.
There is no recipe for finding a mentor but a great deal of it involves being open. There are a few things to remember. One is that mentoring is not always (in fact rarely is) about someone patting you on the head and praising your cleverness. Another is that the people with the greatest skills and experience are not always the people running the firm (often it would be a waste of their talent to be doing so). A final thing to remember is that many of the most skillful lawyers are in the ranks of the younger partners and these are the lawyers who will potentially be seeing the most of you. The QC's in their sixties will be in your life for five to ten years and there will be many ranks of lawyers between you and them. The lawyers in their late thirties and early forties will be the ones who may be with you for the next thirty years -- they may see more of you then their spouses. In many ways it is them that have the greatest interest in seeing you become good (if nor no other reason than it will keep the number of claims against the firm down). Do not have preconceived ideas of who your mentor will be -- you never know where your Bert McKinnon will come from.