arson, our son

Arson or arson means the crime of intentionally burning a building or property--
It was a five-alarm fire; the fire chief suspects arson.
Arson is one of the major felonies, along with murder, kidnapping, and armed robbery.

Our son or our son ( two words ) means the male offspring ( son) belonging to the speaker and one other person ( our )--
Our son will graduate next year.
They would like their daughter to meet our son.

Now that you know that, you can say--
"Our son was accused of arson, but he claims that he's innocent."