According to author Tim Wu, four industries have been identified as “public callings”: telecommunications, banking, energy, and transportation. Utilities such as water and sewage companies could be added to the list. “Each plays an essential role in the workings of the nation and the economy, and thus these are the industries that have attracted regulation as common carriers, or infrastructure.” The quote comes from The Master Switch: The Rise and Fall of Information Empires (Knopf 2010) at 58. If the government does not in fact own and operate major segments of those industries, as in socialist regimes and corporatist governments, it intervenes, directs, and enforces in a commanding fashion for many of these industries.
In the United States, common carriers face thickets of regulations and oversight, laden with laws, regulations, and quasi-judicial proceedings. All things being equal, we might expect law departments in those industries to have not only more lawyers per billion dollars of revenue than non-common carriers but also different mixes of lawyers within the department. Their government affairs function, especially, may swell.
Prof. Wu, I should point out, might make an argument to the contrary. Regulations and the cozy succorance of the government might lessen some legal risks, such as antitrust, pricing conspiracies, quality standards, or even liabilities. Full-throated competitors may require more legal support than cosseted carriers.