Subtleties: Because of and Due To

Today I consider the subtle difference between “due to” and “because of”. Let's ignore the habit that many writers have of adding “the fact that” to these phrases. That's simple fluffery and deserves no quarter here. Consider the following:

Mike succeeded because of his dedication.
Mike's success was due to his dedication.

“Because of” modifies verbs, as seen in the first example. That makes it an adverb, for those of you who care about labels. “Due to” acts as an adjective. Why? No one seems to know, or particularly care, from what I could find. Apparently this question was debated a hundred years ago, but no clear winner arose.

Until the dust settles, consider this was to decide which phrase to use: eliminate the phrase and ask why. For the first sentence above, you'd be left with “Mike succeeded.” Why? “Because of his dedication.” You don't need a full sentence to answer the question, just the phrase you removed.

The second sentence would read, “Mike's success was.” Asking why makes no sense, here. Thus, you would use “due to”.

If you've been paying attention, you'll notice that “due to” follows “to be” verbs and act as predicate adjectives. I've tried to find or write an example in which that did not happen but have not found one. You should care because that means that “due to” lives in passive sentences, generally if not strictly. If you've read this blog before, you know how strongly I feel about avoiding the passive voice.

If you can think of or find an example that proves me wrong, please post it in the comments. And I do realize that "fluffery" isn't a word. I was only testing you.