“Where the technology is going to be in three to five years is the really interesting question,” said Ben Allgrove, a partner at Baker McKenzie, a firm with 4,600 lawyers. “And the honest answer is we don’t know.”

Dana Remus, a professor at the University of North Carolina School of Law, and Mr. Levy studied the automation threat to the work of lawyers at large law firms. Their paper concluded that putting all new legal technology in place immediately would result in an estimated 13 percent decline in lawyers’ hours.

A more realistic adoption rate would cut hours worked by lawyers by 2.5 percent annually over five years, the paper said. The research also suggests that basic document review has already been outsourced or automated at large law firms, with only 4 percent of lawyers’ time now spent on that task.

Their gradualist conclusion is echoed in broader research on jobs and technology. In January, the McKinsey Global Institute found that while nearly half of all tasks could be automated with current technology, only 5 percent of jobs could be entirely automated. Applying its definition of current technology — widely available or at least being tested in a lab — McKinsey estimates that 23 percent of a lawyer’s job can be automated.

Technology will unbundle aspects of legal work over the next decade or two rather than the next year or two, legal experts say. Highly paid lawyers will spend their time on work on the upper rungs of the legal task ladder. Other legal services will be performed by nonlawyers — the legal equivalent of nurse practitioners — or by technology.