The fracas in Janesville was only one example of the aggressive tactics Trump’s security has been using to tamp down even peaceful protests. A POLITICO investigation revealed that Trump has assembled a privately funded security and intelligence force with a far wider reach than other campaigns’ private security operations: tracking and rooting out protesters, patrolling campaign events and supplementing the Secret Service protection of the billionaire real estate showman during his nontraditional campaign for the GOP presidential nomination.

The investigation ― which utilized Federal Election Commission reports, state licensing records, court filings and interview accounts or testimony from more than a dozen people who’ve crossed paths with Trump’s security ― found that the tactics of Trump’s team at times inflamed the already high tensions around his divisive campaign, rather than defusing them.

The Trump campaign could be forced to publicly justify its security tactics in June when a New York state court is set to hear a little-noticed case brought by a handful of protesters who allege they were assaulted by five Trump security officials during a raucous protest outside the campaign’s Manhattan headquarters in September. The protesters’ lawyers have asked the Trump campaign to release its contracts for security, its guidelines for use of force, its security team’s personnel records, and complaints against its members ― including for excessive force, assault, battery or “violation of any federal or state constitutional right.”

Among Trump critics who’ve had run-ins with his security, complaints include unnecessary force, discriminatory profiling and removing people from events based on little more than their appearance.