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Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
by law
Grammar usage guide and real-world examplesUSAGE SUMMARY
"by law" is a correct and usable phrase in written English.
It is a preposition that is used to indicate that something is mandatory or required because an applicable law states it. For example: employers must provide a safe working environment for their employees by law.
✓ Grammatically correct
News & Media
Encyclopedias
Science
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
60 human-written examples
By law".
News & Media
By law, answering is voluntary.
News & Media
Pandora's are set by law.
News & Media
Paraguay prohibited it by law.
Encyclopedias
A bunker mentality is codified by law.
News & Media
By law, they have to do this.
News & Media
By law, hospitals must provide emergency care.
News & Media
They have to do so by law.
News & Media
This is clearly barred by law.
News & Media
Whistle-blowing is required by law.
News & Media
Some endangered species are protected by law.
Encyclopedias
Expert writing Tips
Best practice
Use "by law" to clearly indicate that a requirement or action is legally mandated, ensuring there is no ambiguity about its obligatory nature.
Common error
Avoid assuming that all ethical or recommended practices are mandated "by law". Always verify the legal basis before asserting that something is a legal requirement.
Source & Trust
82%
Authority and reliability
4.6/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "by law" functions as a prepositional phrase that modifies a verb or noun, indicating the legal basis or requirement for an action or condition. It specifies that something is mandated or permitted by legal statutes, as evidenced by Ludwig's numerous examples.
Frequent in
News & Media
37%
Science
31%
Encyclopedias
7%
Less common in
Wiki
6%
Formal & Business
0%
Reference
0%
Ludwig's WRAP-UP
The phrase "by law" is a common and grammatically sound way to express that something is legally required or permitted. As confirmed by Ludwig, it functions as a prepositional phrase, and finds frequent use in news, science, and encyclopedic content. To enhance clarity, ensure you're accurately representing legal requirements and verifying any claims about legal mandates. Alternatives such as "according to the law" or "as required by law" can offer variety while maintaining the core meaning. When writing, remember that not all ethical or recommended actions are mandated "by law"; always confirm the legal basis.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
according to the law
Focuses on adherence to legal principles rather than direct legal mandate.
as required by law
Emphasizes the obligatory nature of an action due to legal requirements.
under the law
Highlights the legal framework within which something operates or is governed.
legally required
Directly states the legal obligation to perform an action.
mandated by law
Stresses that the law specifically orders or commands something.
prescribed by law
Implies that the law has explicitly detailed or specified something.
statutorily required
Emphasizes that the requirement comes from a specific statute or legislative act.
de jure
A Latin term meaning "by right" or "according to law," often used in formal or legal contexts.
in accordance with the law
Highlights compliance and conformity with legal standards and regulations.
as per the legal code
Refers specifically to the written legal statutes or codes.
FAQs
How can I use "by law" in a sentence?
Use "by law" to indicate that something is required or permitted by a legal statute or regulation. For example, "Employers are required to provide a safe working environment "by law"".
What are some alternatives to saying "by law"?
You can use phrases like "according to the law", "as required by law", or "under the law" to convey similar meanings.
Is it correct to say "legally required" instead of "by law"?
Yes, "legally required" is a correct and often interchangeable alternative to "by law", directly stating the legal obligation.
What is the difference between "by law" and "in accordance with the law"?
"By law" directly states a legal mandate, while "in accordance with the law" emphasizes compliance and conformity with legal standards, implying adherence to legal requirements.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
82%
Authority and reliability
4.6/5
Expert rating
Real-world application tested