A Maryland redistricting-reform activist wears a T-shirt showing the state’s convoluted 3rd Congressional District. (Kate Patterson/For The Washington Post)

A lawyer for Maryland’s General Assembly has cast doubt on the legality of Gov. Larry Hogan’s proposal to take politics out of the redistricting process by shifting control from the governor and legislature to a nonpartisan commission.

The idea of using an independent board to draw voting districts is broadly popular among Marylanders, regardless of demographics and political leanings, according to a recent Goucher College poll.

But Assistant Attorney General Kathryn M. Rowe, responding to a request for advice from Sen. Joan Carter Conway (D-Baltimore), said in a letter this month that she has identified 10 legal problems with the proposal by Hogan (R), which would amend the state Constitution to require that a nonpartisan commission handle the redistricting process.

The goal of the legislation is to end the practice of gerrymandering, or manipulating legislative and congressional boundaries in ways that give one party an advantage.

The March 14 letter from Rowe effectively provides ammunition for Democratic leaders in the legislature who have resisted Hogan’s proposal and called for national redistricting changes that would apply equally to states where Republicans control the legislatures.

Hogan’s proposal would have to be approved by the state’s Democratic-majority legislature and by voters to become law. The legislation has stalled at the committee level in the House and Senate, eliciting criticism from Hogan.

Rowe, deputy counsel for the General Assembly, said the proposed constitutional amendment, which provides the governor and legislature with no role in the redistricting process, contradicts another section of the bill that says the final map has to be approved by the General Assembly and the state’s chief executive.

She also took issue with a provision that would require both chambers of the legislature to approve the commission’s redistricting plans by a three-fifths vote. She said no such supermajority rule can apply to regular bills without a constitutional amendment.

Additionally, Rowe said the legislation would restrict the attorney general’s constitutional authority to prosecute or defend the state in all cases pending in Maryland appeals courts and the federal judiciary. The bill would give the nonpartisan panel sole authority for determining who should defend any adopted redistricting plans.

Another concern is that the bill would require funding in the state budget to pay for legal defenses of the final redistricting map. Rowe said the provision “does not meet the requirements necessary under the Constitution to act as a funding mandate” because it does not prescribe a dollar amount or a specific funding formula.

Hogan spokesman Doug Mayer called Rowe’s letter “a feeble attempt to throw up a last-minute smoke screen in front of an important legislative issue.”

He said lawmakers could have addressed the issues Rowe raised by adding amendments to the bill, noting, “that’s what committee hearings are for.”

Maryland is home to some of the most gerrymandered voting districts in the nation, according to many analysts. The state’s 3rd Congressional District is notorious for its design, with lines that meander through four counties in the central part of the state with little geographic sense.

Republicans have accused the previous governor, Martin O’Malley (D), of further manipulating the system in 2011 when he divided many conservative-leaning counties into multiple districts and shifted left-leaning populations from liberal to more moderate districts, all but ensuring that Democrats would control seven of the state’s eight congressional seats.

In Virginia, Democrats say the Republican-controlled legislature has similarly used the redistricting process to its advantage, drawing lines that ensure a lopsided number of GOP congressional representatives. Virginia’s congressional districts are being challenged in the U.S. Supreme Court.

Six states, including California and Arizona, use nonpartisan redistricting commissions to set their voting boundaries.