ride shotgun

To accompany the driver of a vehicle on a journey as an armed escort (originally with a shotgun); (by extension) to accompany someone in order to assist and protect.

“He attended the meeting to ride shotgun for the sales team, in case anyone had a technical question.”

(by extension) To ride in the front passenger seat of a vehicle, next to the driver.

“When both kids want to ride shotgun with Mom, they’ll just have to take turns.”

(by extension) To supervise a process and watch for any risks.