As you can see from these charts, very few states have a downward trend in daily case numbers (per capita, logarithmic). States should have 14 days of downward trending case numbers before allowing more freedom for people to gather.
Given the photos from Memorial Day weekend, many states should show an upward movement in cases in two weeks. If they do not, that will be a good sign, assuming testing is taking place.
See the newsletter, COVID-19 Memo from a news hound, 25 May 2020