This HTML is generated by the Jetpack Contact form module.

The relevant shortcode is this:

[contact-field label="Was a police report filed?" type="radio" options="Yes,No"]

It looks like this changed the HTML markup intentionally:
Automattic/jetpack#34147

Unfortunately, the twentyten theme styles legends differently than labels, and I'm not sure Jetpack should expect otherwise.

Additionally the above PR added an extra fieldset, so now it's fieldset > fieldset which results in the double padding and margins.

The fix required here is going to be a bunch of CSS styles that override twentytens styles, and/or a jetpack bug report to revert/change the behaviour.

I did not find a problem with the Jetpack form in my own WordPress installation, so Automattic/jetpack#34147 seems to have fixed the Jetpack plugin. In my test, the group has one fieldset with a visible legend as its first child element, and each option has a visible label programmatically connected to its button.

However, the WordCamp site has temporary tweaks from #874 that probably do not belong there anymore.

The first item ("Yes") needs to be a label for the radio button, and the screen-reader-only styles for legend elements are not appropriate on the Incident Report page (any other forms likely should not hide the legend either).