By Lawrence Hurley
WASHINGTON, June 26 (Reuters) - The U.S. Supreme Court is set to issue rulings on Thursday in major cases on the Trump administration's bid to add a contentious citizenship question to the 2020 census and efforts by voters to curb the partisan manipulation of electoral district boundaries, a practice known as gerrymandering.
The court has five cases left to decide during its current term, which began in October and ends on Thursday, with the final decisions on tap. The rulings in legal challenges to the proposed census question and partisan gerrymandering could have enduring effects on elections for seats in the U.S. House of Representatives and state legislatures.
Critics have called the move by President Donald Trump's Commerce Department to add a citizenship question to the census a Republican scheme to deter immigrants from taking part in the population count for fear of deportation. The aim, these critics have said, is to engineer a deliberate undercount of places with high immigrant and Latino concentrations, costing Democratic-leaning areas seats in the House to the benefit of Republicans and non-Hispanic whites.
In April's argument in the case, the court's conservative majority appeared to be inclined to rule in favor of Trump.
Separate cases from North Carolina and Maryland focus on whether the justices will empower courts to impose restrictions on partisan gerrymandering, the practice in which electoral districts are drawn purely to amplify the political power of the party already in control of a state's legislature.
Boundaries for House districts and those in state legislatures are redrawn every decade to reflect population changes measured by the census. During arguments in March, conservative justices signaled skepticism toward allowing judicial intervention to rein in gerrymandering while liberal justices seemed supportive.
The court also is due to rule on whether police need a court-issued warrant to draw an unconscious suspect's blood and on whether to greatly expanding the area considered as part of a Native American reservation in Oklahoma.
For a graphic on major Supreme Court rulings, click https://tmsnrt.rs/2V2T0Uf
(Reporting by Lawrence Hurley; Editing by Will Dunham)
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