WASHINGTON — Twitter’s CEO says the company isn’t biased against Republicans or Democrats and is working on ways to ensure that debate is healthier on its platform.

In prepared testimony released before a House hearing Wednesday, Jack Dorsey says he wants to be clear about one thing: “Twitter does not use political ideology to make any decision.”

The testimony comes as some Republicans say conservatives have been censored on social media.

Dorsey offered an explanation of how San Francisco-based Twitter uses “behavioral signals,” such as the way accounts interact and behave on the service. Those signals can help weed out spam and abuse.