Voters in Mississippi head to the polls Tuesday to cast their ballots in a run-off Senate race between Republican Cindy Hyde-Smith and Democrat Mike Espy. The 2018 midterm elections have not been without controversy. In tight races in Florida and Georgia, Republicans protecting slim margins tried to prevent recounts by making unproven claims of voter fraud. The national focus on voting rights prompted us to take a look at Massachusetts' own laws around voter I.D. requirements and recounts. WGBH's Morning Edition anchor Joe Mathieu spoke about this with Legal Analyst and Northeastern Law Professor Daniel Medwed. The transcript below has been edited for clarity.

Joe Mathieu: Now that we've heard the stories of other jurisdictions about onerous voter I.D. requirements that are making national news, what are the rules here in Massachusetts about this?

Daniel Medwed: Well, Massachusetts law provides that poll workers may ask for voter I.D. under very particular circumstances, such as if it's your first time voting in a federal election in Massachusetts, or you've been an inactive voter in the past. But the good news is that a wide range of documents would satisfy this requirement — basically anything with your name and address, like a recent rent receipt or a recent utility bill. Now one provision that caught my eye, is that poll workers may ask for I.D. in other situations, where they have reasonable suspicion of a problem.

Mathieu: Could that provision possibly be used to discriminate against certain voters? That's frequently the concern.

Medwed: In theory, it's possible that poll workers could exploit the ambiguity of that language to discriminate. But in practice I don't think it will happen that often, because courts are very vigilant in interpreting phrases like reasonable suspicion or reasonable cause in an objective manner, to safeguard against discrimination. I also think it's important to have a safety valve like this to give flexibility to poll workers during those very, very rare instances of possible voter impropriety.

Mathieu: So let's turn to recounts. Under what situations may a candidate actually initiate one here?

Medwed: In Massachusetts it varies considerably, depending on the type of election, whether it's a statewide, local or district-wide election. So, for a statewide election, an aggrieved candidate may petition for a recount if the margin of victory is within one half of one percent, and they garner, I believe, 1,000 signatures from voters. For a district-wide race, it's the same basic rule, except the number of signatures varies. I think you have to get one-quarter of the number of signatures you'd have to have on your nominating papers. And for local races, it varies even more depending on the particular municipality. Boston, for instance, has very different rules from other cities and towns.

Mathieu: We're talking with WGBH News Legal Analyst and Northeastern Law Professor Daniel Medwed. Can voters themselves, as opposed to candidates, actually initiate a recount?

Medwed: That's a really important question. And the short answer is, yes. Voters may request a recount, but only for ballot questions, not for elected representatives. So if the discrepancy between a negative and an affirmative vote on a particular ballot question is within one half of one percent, then the people may petition for a recount, subject to signature requirements.

Mathieu: So if that happens, a recount is properly initiated, what does the process look like?

Medwed: Well it looks like the picture of chaos. We actually have a recent example of this, because back in September, there was a recount in a very razor-thin election at the Democratic primary for the 3rd Congressional District out in Merrimack Valley — Lawrence, Lowell, Andover — where Lori Trahan and Daniel Koh were separated by 122 votes.

Koh petitioned for a recount. And that triggered a very painstaking five-day process, where — get this — election officials in, I believe, 37 cities and towns hand counted 89,000 ballots. I mean, literally, people took magnifying glasses and looked at the little ovals on the ballot to see whether they were accurately filled out and could go through the optical scanner. Secretary of State William Galvin even intervened to supervise a situation in Lowell and Lawrence because of some concerns out there. The upshot is that Trahan picked up 23 votes. She ended up winning by 145 and later sailed to election in the general in November. But even so, I think recounts serve a very vital purpose. Even though they seldom result in a reversal of the outcome, they can serve to validate the integrity of the process and provide a sort of audit function.