Justice Department officials are warning that they’ll be dispatching fewer trained election observers as a result of a Supreme Court opinion that gutted a key provision of the Voting Rights Act.

The reduction is likely to diminish the department’s ability to detect voter intimidation and other potential problems at the polls. It comes as more than a dozen states have adopted new voting and registration rules, and as Republican candidate Donald Trump warns without evidence that the Nov. 8 election will be rigged and exhorts his followers to be vigilant against unspecified fraud.