This is a serious abuse of executive power and possibly a federal crime. The Trump admin. was notorious for targeting perceived enemies, but it thoroughly crossed the line here. There must be detailed investigations into these audits.
Though it is easy to jump to conclusions, a proper investigation must be undertaken to determine if any wrongdoing occurred. It is possible that these audits were politically motivated, but there are correct procedures for dealing with such accusations, and they must be followed.
This isn't the first time that a presidential administration has been accused of weaponizing the IRS. And regardless of whether or not it turns out that Trump singled out Comey and McCabe, this scandal should help awaken Biden to the need to reform and better support that vital but unpopular office.