Labor unions' tyranny at construction sites was shown in a recent survey.

In a two-week poll of construction companies, conducted by the Construction Association of Korea, the Korea Housing Association and the Korea Specialty Contractors Association at the request of the Ministry of Land, Infrastructure and Transport, 843 construction companies reported that they suffered setbacks in construction projects due to high-handed action from labor unions.

Considering that some companies may have avoided disclosing damage inflicted by labor unions for fear of retaliation, the real number of cases could be much higher.

The ministry plans to check the reports made through the survey and ask law enforcement to investigate.

In most cases, construction companies were coerced by unions into hiring their members and using their equipment.

When a builder rejected a construction union's demand to employ its members at its housing construction site, the union blocked the supply of ready-mixed concrete to the site, stopping the construction.

To make matters worse, companies are said to have their money taken by union members in all sorts of names, such as express charges, union development funds and welfare expenses.

Land Minister Won Hee-ryong seems to have hit the nail on the head when he called them hoodlums dressed as unionists.

It has become common practice for construction subcontractors to pay tower crane operators unofficial monthly allowances of millions of won, separately from their official wages. A company reported paying 1.3 billion won ($1.04 million) in such allowances to tower crane operators at five construction sites.

If a company refuses to pay the allowance, tower crane operators are said to lift building materials and equipment slowly or refuse to raise them, citing safety concerns.

Some unions demanded money under absurd pretexts. A construction site manager reported signing a written agreement to donate to a union fund and giving the union millions of won because they threatened to keep filing complaints to local authorities regarding construction sites until they receive the donation.

If unions' demands are rejected, they obstruct business by blockading construction sites and staging illegal protests. Companies say they often pay compensation for construction delays due to unions' obstruction of business.

These evil practices inflict damage not only on construction companies, but also on people in the form of construction delays, shoddy and faulty construction and increased construction costs.

In the construction industry, there are scores of unions in addition to company unions. Some of them are affiliated with the nation's two largest labor groups -- the Korean Confederation of Trade Unions and the Federation of Korean Trade Unions, but some, including ones of workers based in specific regions, are not.

Illegal labor behavior at construction sites did not start yesterday. They have been around for years, but companies were reluctant to report them for fear of backlash and retaliation from unions. Constructors had no choice but to accept demands, even though they were unlawful, out of concern for construction delays and cost increases.

The problem with construction unions has been brought up many times but the government has been passive about dealing with them. Punishment is usually no more than a slap on the wrist. The Korean Confederation of Trade Unions habitually stood against the government at the slightest provocation, criticizing it for suppressing labor unions. In the end, illegality has become a custom.

Illegal union activity at construction sites must not be neglected any longer. The government must respond more actively. The problem nibbles away at industrial competitiveness and threatens people's lives and properties.

The government needs to set up reporting centers and receive reports on unlawful union behavior all year round. Local authorities must probe damage cases in cooperation with law enforcement. Above all, retaliatory acts must be stamped out.

President Yoon Suk Yeol emphasized labor reform and the rule of law in his New Year address. Rooting out unlawful labor tyranny at construction sites should be the starting point of reform and the rule of law. A strong will, a continuous crackdown and a tough punishment are needed.