Denver Mayor Mike Johnston on Wednesday agreed to testify before Congress over Denver's status as a sanctuary city. Why it matters: Johnson will be pressed to defend Denver's policies protecting migrants from deportation at a time when the U.

Denver Mayor Mike Johnston has decided to testify before a congressional committee next month after its members asked him to travel to Washington, D.C., to explain the city’s policies limiting cooperation with federal immigration authorities.

Denver Mayor Mike Johnston on Wednesday announced he would attend a congressional hearing for an investigation into so-called sanctuary cities.