Eh? No; the US works broadly the same. For instance, a rather amusing recent one: https://www.cnbc.com/2023/08/31/tesla-reportedly-facing-doj-...

The “probe” here would be, at least in the first instance, usually mostly letters asking questions. Note that it is “reportedly”; the media didn’t find this out because the DOJ had a banner on its website saying “we are investigating an alleged glass house”. That comes later, if things are not resolved.