President Donald Trump’s push to deploy National Guard troops to Democrat-run cities is gathering strength despite a wave of lawsuits and conflicting rulings from federal judges, as legal experts say his administration is finding firmer constitutional footing to protect federal property and personnel.

Constitutional law expert John Shu told the Washington Examiner that the administration’s strategy, limiting National Guard activity to defensive missions around federal sites, places the president on strong legal ground even as states such as Illinois, Oregon, and California attempt to block the deployments. Trump’s moves follow weeks of agitation and unrest by protesters at Immigration and Customs Enforcement facilities and around personnel conducting immigration removal efforts, which the administration has said threatens the safety of federal agents and the surrounding areas.