More large law firms are spreading the word about their medical cannabis practice capabilities as ethics rule changes and state legislation whittle down the amount of risk involved in providing that guidance. And in Pennsylvania, which is poised to be a center for clinical marijuana research, lawyers expect a major payoff for firms that get involved in the budding industry.

Entering the space still requires firms to weigh the fact that cannabis remains illegal under federal law. For some, malpractice insurance or perceptions of other clients have been a concern. But law firm leaders and practice leaders said those concerns are lessening as the law firm growth opportunities increase.