The verdict on a government bid to establish a fully elected upper house had been keenly anticipated, with thousands of pro- and anti-government protesters massing in the capital.
Bangkok has played host to periodic outbreaks of street violence in recent years and hundreds of riot police were in and around the court ahead of its ruling.
Judges slammed Prime Minister Yingluck Shinawatra's party for driving through the change to the charter -- drawn up under the military junta that deposed her divisive brother Thaksin -- calling it "unconstitutional".
The scuppered proposal to make the upper house fully elected would have returned the senate to its structure before the 2006 coup that removed Thaksin and ushered in a period of political turmoil.
In its ruling, the bench criticised the process of pushing the amendment through, but "dismissed the petition to dissolve" Puea Thai and its coalition partners.
A verdict that the ruling party acted unconstitutionally could have triggered its dissolution by the court, with leading MPs facing five-year bans from politics.
Analysts said that would have enraged the government's supporters, including the powerful "Red Shirts" who have massed in their tens of thousands since yesterday in a stadium in the city suburbs.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →
Smart Quarterly
₹900
3 Months
₹300/Month
Smart Essential
₹2,700
1 Year
₹225/Month
Super Saver
₹3,900
2 Years
₹162/Month
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Exclusive premium stories online
Over 30 premium stories daily, handpicked by our editors


Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share


Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor


Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements


Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
